[P6] Problem Sum No. 8: Muffins in Boxes

Ali sold muffins in boxes of threes and fours. At first he had 5 times as many small boxes as big boxes. After selling 2/5 of the small boxes and some big boxes, he packed another 12 more big boxes. As a result the number of unsold small boxes became twice the number of unsold big boxes. If the total of unsold muffins was 150 how many big boxes did he sell? Asked by wife’s colleague, Lilian Date: 18...

[P6] Problem Sum No. 7: Simon’s and Peter’s Cards...

Simon and Peter had a total of 900 cards. Simon gave 1/5 of his cards to Peter. Peter then gave 1/4 of his cards to Simon. In the end, each of them had the same number of cards. How many cards did Simon have at first? Asked by Dave Tan KX (of North Vista Primary School) Date: 25 Feb 2016 Source: Nan Hua Primary, P6, CA1 2014 In case you haven’t seen it, our No Problem Sums Facebook page...

[P6] Problem Sum No. 5: Sum of Digits

A certain two-digit number is 3 times the sum of its digits. What is this number? Asked by Mark Heng Date: 26 May 2013 Source: www.algebra.com; adapted, P6 This type of problem sum certainly looks tricky — doesn’t seem like there are many clues. And it is tempting to think of one general method to solve it: Algebra! Parents, was algebra the first thing that came to your mind? Do you think there could be simpler ways to tackle...