Answer :
It varies directly, so the ratio of the age to the height is constant.
2 weeks old - 38 cm tall
3.5 weeks old - x cm tall
[tex]\frac{2}{38}=\frac{3.5}{x} \\ 2x=3.5 \times 38 \\ 2x=133 \\ x=66.5[/tex]
A sunflower plant that is 3 and a half weeks old is 66.5 centimeters tall.
2 weeks old - 38 cm tall
3.5 weeks old - x cm tall
[tex]\frac{2}{38}=\frac{3.5}{x} \\ 2x=3.5 \times 38 \\ 2x=133 \\ x=66.5[/tex]
A sunflower plant that is 3 and a half weeks old is 66.5 centimeters tall.