Lessons · page 21 2161Multiplying bigger numbers in stories3 sentences · When there are many equal groups, multiply the number of groups by the size of one group, even when both are…162Dividing bigger numbers in stories3 sentences · Dividing tells how many equal groups there are, or how many go into each group, when the total is large.163Moving towards each other and moving apart3 sentences · When two travellers move towards each other, the gap between them shrinks by both their speeds together ever…164Catching up4 sentences · When a faster traveller chases a slower one going the same way, the gap shrinks by the difference of the spe…165Working together3 sentences · When two teams work at the same time, their work for one day adds up: what both do together in a day is the…166Chickens and rabbits: heads and legs4 sentences · Suppose every animal were a chicken: then there would be 2 legs for each head.167Chickens and rabbits in disguise: wheels, tickets, boats3 sentences · Any story with two kinds of things, a total count and a total of something else, is a chickens and rabbits p…168The score that makes the average3 sentences · An average of 80 over 4 tests means the 4 marks add up to 4 × 80 = 320.169Working alone first, then together3 sentences · When one team starts alone and the other joins later, first take away the work done alone, then share the re…170The dog that runs back and forth4 sentences · Do not follow each trip of the dog: only ask how long it runs.171The unknown on both sides of a story3 sentences · Sometimes the unknown number appears twice: 3 bags and 5 more weigh as much as 1 bag and 21 more.172Working backwards through three steps3 sentences · To find the start, begin with what is left at the end and undo the steps one by one, from the last to the fi…173A part, then a part of the rest2 sentences · A ribbon is 60 cm. 1/3 is cut off: 60 / 3 = 20 cm, and 40 cm remain.174Too many or too few: surplus and shortage5 sentences · If each child gets 3 pencils, 5 are left over; if each gets 4, 2 are missing.175Two circles: both and neither5 sentences · Draw two overlapping circles.176Which row? Steps that grow by the same number4 sentences · When each row has the same number more than the row before, row N has the first row plus N - 1 steps.177Adding all the rows4 sentences · When rows grow by the same number, pair the first row with the last, the second with the one before the last…178Days of the week after many days5 sentences · Number the days of the week: Monday is 1, Tuesday 2, …, Sunday 7.179Two circles: how many are in both?3 sentences · Those who are in at least one circle are the whole group without those in neither circle.180Olympiad puzzle: how many pages from the digits?5 sentences · Numbering pages from 1: pages 1 to 9 use 9 digits, pages 10 to 99 are 90 pages of 2 digits, 180 digits; toge…181Sure of several of the same colour3 sentences · To be sure of something, think of the unluckiest draw: it takes as many as it can without the wish coming tr…182Sure of one of each of two colours4 sentences · To be sure of a red one and a blue one, imagine the worst luck: all the others come first, and of red and bl…183How many odd numbers in a range3 sentences · Odd and even numbers take turns, so in a range about half of the numbers are odd; the ends decide whether it…184Two-digit numbers with a given digit sum4 sentences · A two-digit number has a tens digit from 1 to 9 and a ones digit from 0 to 9; count the numbers by trying ea…185Cuts and pieces3 sentences · Cutting a log or a ribbon into pieces always takes one cut fewer than the number of pieces: the last piece n…186Balancing the scales6 sentences · When the scales balance, both pans weigh the same.187When together again4 sentences · Two things that repeat meet again at the smallest number that is a multiple of both repeat times.188The longest equal pieces2 sentences · To cut two lengths into equal pieces with nothing left, the piece must divide both lengths; the longest such…189Crossing the river with one boat4 sentences · The boat cannot cross empty, so after every trip across except the last one somebody must row it back.190Who am I? Number riddles4 sentences · A riddle about a two-digit number gives facts about its digits; find the digits from the facts and put them…191The comparison model: times as many, and the total3 sentences · Draw the smaller amount as one bar, a unit.192A whole in three parts5 sentences · When a whole is made of three parts, the parts add up to the whole.193Change after buying several things4 sentences · First find what each kind of thing costs in all: the price of one times how many.194Adding hours and minutes4 sentences · Add the hours to the hours and the minutes to the minutes.195Metres and centimetres in several steps3 sentences · One metre is 100 centimetres.196Before and after: giving to make equal5 sentences · When one child gives things to another, the total stays the same.197The area of an L-shape4 sentences · An L-shape is a rectangle with one corner missing.198Exam 1: two exchanges3 sentences · If A then has 3 times as many as B, the gap is 2 of B's units: one unit is 24 ÷ 2 = 12.199Exam 2: some left over, some missing4 sentences · Sharing p each leaves some over; sharing q each leaves some missing.200Exam 3: heads, and a difference of legs5 sentences · Chickens have 2 legs, rabbits 4.201Legs on insects and spiders3 sentences · Every insect has 6 legs: ants, beetles, bees, ladybirds and grasshoppers all walk on 6 legs.202Legs on four-legged animals3 sentences · Dogs, cats, mice, lions, giraffes, horses, tortoises and lizards each walk on 4 legs.203Legs on birds, and animals with none3 sentences · Every bird has 2 legs: chickens, ducks, penguins, owls and parrots stand on 2 legs.204Wings on birds and on insects3 sentences · A bird has 2 wings: ducks, owls, chickens and every other bird.205Legs on a mixed farm3 sentences · On a farm, cows, pigs, sheep and goats walk on 4 legs, while chickens and ducks stand on 2.206Hooves and horseshoes3 sentences · A horse has 4 legs, and each leg ends in a hoof, so a horse has 4 hooves.207Fingers and toes4 sentences · A person has 2 hands with 5 fingers each, so 10 fingers, and 2 feet with 5 toes each, so 10 toes.208Eyes, ears and hands3 sentences · Every person has 2 eyes, 2 ears and 2 hands, but only 1 nose.209People and animals together3 sentences · A person walks on 2 legs, while a dog, a cat or a sheep walks on 4.210Counting back from heads and legs, cycles and wheels4 sentences · Cows have 4 legs and chickens 2.211Teeth of grown-ups and children3 sentences · A young child with all the first teeth, the milk teeth, has 20 of them.212Pairs and odd socks3 sentences · A pair is two things that go together: a pair of socks is 2 socks, a pair of shoes is 2 shoes.213A pair for each person3 sentences · Each person has two feet and two hands, so each person wears a pair: 2 shoes, 2 boots, 2 gloves.214Sleeves in the wash2 sentences · A sweater, a coat, a shirt with long sleeves — each has 2 sleeves, one for each arm.215Clean socks for a week4 sentences · A week has 7 days.216Legs on tables and chairs3 sentences · An ordinary chair stands on 4 legs, and an ordinary table stands on 4 legs too.217Corners of bunting flags3 sentences · A triangle has 3 corners and 3 sides; a square and a rectangle each have 4 corners and 4 sides.218Fence around a square3 sentences · A square has 4 sides, and all 4 sides are the same length.219Wheels on cycles4 sentences · A unicycle has 1 wheel, a bicycle has 2 and a tricycle has 3: «uni» means one, «bi» two, «tri» three.220Riders on tandems and bicycles3 sentences · A tandem is a bicycle made for two: it has 2 seats, one behind the other, and 2 wheels like an ordinary bicy…221Days and weeks3 sentences · A week has 7 days, from Monday to Sunday, and then the next week begins.222Fortnights and school weeks3 sentences · A fortnight is two weeks, so it is 14 days.223Days in the months3 sentences · January, March, May, July, August, October and December have 31 days; April, June, September and November ha…224Years, decades and seasons3 sentences · A year has 12 months, 4 seasons of 3 months each, and 52 weeks and a day or two; a decade is 10 years and a…225Hours, minutes and seconds4 sentences · An hour has 60 minutes and a minute has 60 seconds; a day has 24 hours.226How long it takes on the clock3 sentences · To find how long something lasts, count on from the start time to the next o'clock, then on to the end time.227Every day for a week3 sentences · Something that happens every day happens 7 times in a week, because a week has 7 days.228Counting in the classroom3 sentences · When children are put into groups, tables or boats, nobody may be left out: a smaller last group still needs…229The school week3 sentences · A school week has 5 school days, Monday to Friday.230Letters, colours and points5 sentences · The English alphabet has 26 letters.231Players in a team3 sentences · Every sport has its own number of players in a team, and you are expected to know it: a soccer team and a cr…232Teams of rugby and other football2 sentences · A rugby union team has 15 players on the pitch, and so does a Gaelic football team and a hurling team (rugby…233Making teams3 sentences · A volleyball team has 6 players on the court.234Points in a game3 sentences · In basketball a basket scored from inside the line is worth 2 points, a three-pointer 3 points and a free th…235Overs, holes, frames and halves3 sentences · In cricket an over is 6 balls bowled by one bowler.236Dice3 sentences · An ordinary die has 6 faces with 1, 2, 3, 4, 5 and 6 dots.237A deck of cards3 sentences · A full deck of playing cards, without the jokers, has 52 cards: 4 suits of 13.238Board games3 sentences · A chess game starts with 32 pieces on the board, 16 white and 16 black.239Toys, rows and groups3 sentences · Things set out in equal rows are counted by multiplying: rows × how many in each row.240US coins3 sentences · In the United States a penny is 1 cent, a nickel 5 cents, a dime 10 cents and a quarter 25 cents; 100 cents…241Paying with US coins3 sentences · In the United States a dollar is worth 100 cents, and a quarter is worth 25 cents, so 4 quarters make a doll…242Canadian coins3 sentences · In Canada the one-dollar coin is called a loonie, because it has a loon on it, and the two-dollar coin is ca…243British coins and notes3 sentences · In Britain a pound is worth 100 pence, written 100p, and a five-pound note is often called a fiver.244Australian, New Zealand and Irish money3 sentences · A price like $4.50 means 4 dollars and 50 cents, which is 450 cents.245Shopping sums3 sentences · A six-pack holds 6 cans, and a dollar is worth 100 cents.246Best buys and offers3 sentences · A dozen is 12 things, and a dollar is worth 100 cents.247Metres, centimetres and millimetres3 sentences · A metre is 100 centimetres, and a centimetre is 10 millimetres.248Feet, inches, yards, pounds and stone3 sentences · A foot is 12 inches.249Weight and volume in the kitchen3 sentences · A litre is 1000 millilitres, and a kilogram is 1000 grams.250Distances out and about4 sentences · A kilometre is 1000 metres.251Dozens and spoonfuls4 sentences · A dozen is 12.252Recipes and sandwiches3 sentences · A sandwich is made from 2 slices of bread with the filling in between.253Laying the table3 sentences · When a table is laid, every person gets a knife, a fork and a spoon: 3 pieces of cutlery for each person.254Pizzas and cakes for a crowd3 sentences · A large pizza is cut into 8 slices.255Getting everyone there2 sentences · A return ticket takes you there and brings you back: it is 2 journeys.256Candles and party bags3 sentences · A birthday cake has one candle for every year: a child turning 7 gets 7 candles.257Party costs, drinks and time4 sentences · A litre is 1000 millilitres (ml).258Seating and serving the guests3 sentences · At a party every person at the table gets one cup and one plate: that is 2 things for each person.259Laying the party table3 sentences · A table laid in full gives every person 5 things: a plate, a knife, a fork, a spoon and a glass.260Planning the whole party4 sentences · A sandwich takes 2 slices of bread.1 2← previousLanguagenext →Medicine↑ back to the schoolThis page in Markdown → https://md.mova.elamur.ai/free/en/corpora/school/lessons/page/2/