The two markers with a question mark have the same number. Which number do you have to put instead of the question mark so that the calculation is correct?
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Answer: C — 3
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Hint 1 of 3
Both question marks hide the very same number, so whatever you try, use it in both spots.
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Hint 2 of 3
You can just try the answers: put 1 in both marks, then 2, then 3, and check the sum each time.
Still stuck? Show hint 3 →
Hint 3 of 3
Keep trying numbers until the calculation comes out right.
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Approach: try the same number in both marks until the sum works
Remember both marks are the same number, so pick a number and use it in both spots.
Try the choices in turn and add up: too small a number makes the total too low, too big makes it too high.
The number that makes the calculation come out exactly right is 3, so the answer is C.
Logic & Word Problemswork-backwardcareful-counting
Each of the children Ali, Lea, Josef, Vittorio and Sophie gets a birthday cake. The number on top of the cake shows how old the child is. Lea is two years older than Josef, but one year younger than Ali. Vittorio is the youngest. Which cake belongs to Sophie?
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Answer: C
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Hint 1 of 3
There are five cakes with five ages on them — match a child to each one.
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Hint 2 of 3
Use the clues to label the easy children first, and give the smallest cake to Vittorio.
Still stuck? Show hint 3 →
Hint 3 of 3
Sophie gets the one cake that is left over after everyone else is matched.
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Approach: match the easy children first; Sophie gets the leftover cake
Josef, then Lea (2 older than Josef), then Ali (1 older than Lea) line up in a row of ages.
Vittorio is the youngest, so he takes the smallest-numbered cake.
Four children are now placed, so the one cake left over is Sophie's: the cake showing 6, option C.
Maria has a total of 19 apples in 3 bags. She takes the same amount of apples from each bag. Then there are 3, 4 and 6 apples in the bags. How many apples did Maria take from each bag?
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Answer: B — 2
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Hint 1 of 3
First add up how many apples are still left in all three bags.
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Hint 2 of 3
Maria started with 19, so the apples she took are the 19 minus the ones still left.
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Hint 3 of 3
She took the same number from each bag, so share the taken apples equally among 3 bags.
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Approach: find how many were taken in all, then share among 3 bags
Count the apples still in the bags: 3 and 4 and 6 make 13.
Maria began with 19, so the apples she took away are 19 take away 13, which is 6.
She took the same from each of the 3 bags, so share 6 into 3 equal groups: 2 from each bag, option B.
Logic & Word Problemswork-backwardcareful-counting
Three frogs live in a pond. Each night only one of the frogs sings a song. After 9 nights the first frog has sung 2 times. The second frog has listened to 5 songs. How many songs did the third frog listen to?
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Answer: B — 6
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Hint 1 of 3
There are 9 nights and one song each night, so the three frogs together sang 9 songs.
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Hint 2 of 3
On any night, a frog is either singing or listening — so a frog listens on every night it did not sing.
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Hint 3 of 3
If the second frog listened to 5 songs, that tells you how many nights it sang instead.
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Approach: 9 songs in all; a frog listens on every night it does not sing
There are 9 nights with one song each, so 9 songs were sung in all. Frog 1 sang 2 of them.
Frog 2 listened to 5 songs, so out of 9 nights it sang on the other 4 nights.
That leaves Frog 3 singing 9 take away 2 take away 4, which is 3 nights, so it listened on the other 6 nights: 6, option B.
