Use each of the digits 1 to 6.
Put one digit in each box.
What is the smallest product you can make?
What is the biggest product you can make?
Ages 13-15. pt = Travelling in France
Michelle was travelling in a car in France. There were lamp posts at equal intervals along the road.
She noticed that the speed of the car in kilometres per hour was nine times the number of lamp posts the car passed in one minute.
How far apart were the lamp posts?
SOLUTIONS Product Smallest product: 2456 x 13 = 31 928. Biggest product: 6321 X 54 = 341 334. Travelling in France Assume the posts are a distance of d metres apart, and that Michelle passes n posts in one minute. Then the speed of the car in metres per minute is n x d. The speed of the car in kilometres per hour is 9n. So the speed in metres per minute is 9nx 100060 , or 150n. Equating these gives d = 150 metres.