Cody was 165cm y'all on the first day of school this year, which was 10% taller than he was on the first day of school last year. How tall was Cody on the first day of school last year?

Solution:

Let

X = height of Cody on the first day of school last year

Given:

Y = height of Cody on the first day of school year = 165 cm

10% (X) + X=Y

.10 (X) + X=165

1.10X=165

X=165/1.1

X=

150 cm = height of Cody on the first day of school last year