## Category: Middle School

### Minimum time to cross the river – a puzzle

Puzzle Jose, Carlos, Linda, and Anna need to cross a bridge. It was dark and they only have one torch which they need to use to cross the bridge. Each of them have crossed the bridge before alone. Jose can run and cross it for one minute. Carlos can also do it in two minutes….

### Application of Distributive Property

What is the Distributive Property? The distributive property (aka distributive law) is a property of real numbers which says that the product of a number say a and the sum (or difference) of two numbers say b and c, is equal to the sum (or difference) of the product of a and b and a…

### Sum of Consecutive Numbers

Problem 1 Can you work out the answer to this number pattern and explain why you think you have the correct answer? You probably observed that the sum is the square of the middle number. Can you work out why? Why do you have a square number for the sum? Solution 1 Solution 2 Solution…

### How many squares can you form with the dots?

Problem How many squares with whole number areas can you form on this 5 x 5 dot array with the dots for corners?   Solution Hint 1. The figure below is a 4 x 4 grid. It shows squares you probably did not consider when you jumped right away on an answer. Do they also…