Question

The ratios in an equivalent ratio table are 3:12, 4:16, and 5:20. If the first number in the ratio is 10, what is the second number? Justify your reasoning.

Answer 1

10:40 the ratios are increased by multiples of 4.

Answer 2

the 3 ratios given, the bottom number is the top number times 4

3*4=12

4*4=16

5*4=20

so if the top number is 10 the bottom will be 40

10*4 = 40