Agardener a is 7 feet tall and grows at a rate of 11 inches per year: type a is 7 feet tall and grows at a rate of 11 inches per year. type b is 8 feet tall and grows at a rate of 9 inches per year

6 years (assuming the question is how many years it'll take for them to be the same height)

Step-by-step explanation:

You have to first convert the height of the trees into inches. 7 feet will convert into 84 inches and 8 feet will convert into 96 inches. since type a is 84 inches and grows 11 inches a year it'll create the expression 84+11x. Type b will create the expression 96+9x. Since you're looking for how long it'll take you set the expressions up to one another and solve for it.

84+11x=96+9x

-84         -84

11x=12+9x

-9x    -9x

2x=12

x=6

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.