Question

Please please please please help I don’t understand this question

The area of a parallelogram is 240. If the base is reduced to one-fourth its original length and it’s height is doubled, what is the new area?

A. 30
B. 60
C. 120
D. 240

Answer 1

120 units² (Answer C)

Explanation:

The area of a parallelogram of base b and height h is A = bh, and here

A = bh = 240 units².

Doubling the height would give us a new height of 2h, and taking a quarter of the original base (length) would give us a new base (length) of b/4.

240 units²

Solving A = bh = 240 units² for h yields -------------------

b

and then substituting this result for h in the new equation

A = (2h) · (b/4) yields:

240 units² 2 · (240 units²)

(2 · ----------------- ) · (b/4), or ------------------------- = 120 units² (Answer C)

b 4