Weekly Problem

Last week’s answer: 5. 80% of 25 = 20, so there are 20 red tomatoes. Therefore there must be 25 – 20 = 5 yellow tomatoes.

This week’s problem: Adam is 9, Bernard is 12 and Charlotte is 15. Mary joins them, and the average age of the group goes up by two years. How old is Diane?

The answer will be in next week’s weekly problem.

Last week’s answer: 15. The first team will need to play the other five once. The second team will only need to play four more, as they will have already played the first team. The third team plays three, the fourth plays two and the fifth and sixth teams have the last game. Thus the total number of games = 5 + 4 + 3 + 2 + 1 = 15.

This week’s problem: There are 25 tomatoes in a crate. 80% of them are red and the rest are yellow. How many yellow tomatoes are there in the crate?

The answer will be in next week’s weekly problem.

Last week’s answer: It is Monday. If tomorrow’s yesterday is Tuesday, then Tuesday is the day before tomorrow which is today, so today is Tuesday. Yesterday’s tomorrow is the day after yesterday, which is today, which is Tuesday. So the day before yesterday’s tomorrow is the day before today, which is the day before Tuesday, which is Monday.

This week’s problem: Six hockey teams play each other once. How many matches will need to be played?

The answer will be in next week’s weekly problem.

Last week’s answer: 16/20, or 4/5. This is because 1/4 = 5/20, and 11/20 + 5/20 = 16/20.

This week’s problem: Tomorrow’s yesterday is Tuesday. What day is the day before yesterday’s tomorrow?

The answer will be in next week’s weekly problem.

Last week’s answer: Harry will get £1.40 change, as the total amount he spent was 6 x  60p = £3.60. Therefore his change is £5.00 – £3.60 = £1.40.

This week’s problem: What is 1/4 + 11/20?

The answer will be in next week’s Weekly Problem.

Last week’s answer: Each of the other two sides is 60m long. This is because we know that the two sides sum to 200m – 80m = 120m, and therefore if they are the same size then they must both be 120m / 2 = 60m.

This week’s Problem: Harry buys 6 lemons at 60p each. If he pays with a £5 note, how much change will he get?

The answer will be in next week’s Weekly Problem.

Welcome to the Weekly Problem Series, where every week I post an example problem from secondary school maths tests. See if you can do it!

This week’s problem: A field is in the shape of a triangle. It is surrounded by a fence, which is 200m long overall. The longest side of the field has an 80m fence along it. The other two sides are the same length. How long is one of the shorter sides? (Try using a diagram.)

The answer will be in next week’s Weekly Problem.