Question

A tree grows at a rate of $0.5$m/yr. What will be the height of a board fixed at $1.5$m above the base, five years ago?

• A. $4$m
• B. $3.5$m
• C. $1.5$m
• D. $4.5$m

Answer 1

The correct option is C $1.5$m

The rate of growth of the plant is 0.5 m/yr.

After 5 years, the plant height will be 0.5 X 5= 2.5m + 1.5m = 4m

The board was fixed at 1.5 m,

after 5 years, the height of the board will be the new height of the board minus the initial height of the plant with the board, that is, 2.5m-1.5m= 1.5m

Hence, the correct answer is '1.5m'