THIS MONTH'S QUIZ
1. When Mr. and Mrs. Jones were married she was 4/5 of his age. She is now 6/7 of his age, and in seven years' time she will be 7/8 of his age. How long have they been married?
2. A straight fence has its posts equally spaced. If the spacing between adjacent posts had been 10 cm more, one less post would have been required. But if the spacing had been 9 cm less, one more post would have been needed. How long is the fence?
3. Three children at a fair, Andy, Beatrice and Charlie, tried to guess the number of marbles in a jar. Their answers were 200, 220 and 236 (but not necessarily in that order). All three were wrong, but Andy's error was twice as great as Beatrice's, and three times as great as Charlie's. What is the correct number?