Question

When i was 18 years old, my sister was half my age. Now I am 82 years. How old is my sister now?​

Answer 1

41 y/o

Explanation:

its a ratio and proportion:

18 y/o = 82 y/o

9 y/o x

82(9) = 18(x)

x = 738 / 18

x = 41 y/o

Answer 2

`41 \: \: \: years \: \: \: old`

Explanation:

`me \: \: \: \: \: \: \: \: \: \: \: sis \\ 18 \: \: \: \: \: \: \: \: \: \: \: \: 9 \\ 82 \: \: \: \: \: \: \: \: \: \: \: x \\ \\ use \: \: cross \: \\ multipaction \\ \\ 18x = 82 * 9 \\ 18x = 738 \\ (18x)/(18) = (738)/(18) \\ x = 41`