Cody was 165\,\text{cm}165cm165, space, c, m tall on the first day of school this year, which was 10\%10%10, percent taller than he was on the first day of school last year.
How tall was Cody on the first day of school last year?
Assume that Cody was x cm tall on his first day at school last year. Assume that Cody is y cm tall on his first day at school this year. This year, Cody became 10% taller. 10% is equivalent to 0.1
This can be translated into the following: y = x + 0.1x We are given that y = 165 cm. Substitute in the equation to get x as follows: 165 = x + 0.1x 165 = 1.1x x = 150 cm
Based on the above calculations, Cody was 150 cm tall on his first day at school last year.
