Question

the lenght of a rectangle is decrease by 2/5 time its original lenght,find the percentage decrease in its area it the area of the decreased portion of the rectangle is 42m^.find the new area of the decreased rectangle ?

Answer 1

Answer:

Percentage decease in area = 40 %

New Area = 63 m²

Step-by-step explanation:

L- Length W - Width

Area = LW

Length decreased by 2/5 = 2/5 L

New Length = L - 2/5L = 3/5 L

New Area = 3/5LW

Decreased Area = LW - 3/5LW = 2/5LW

2/5 LW = 42 m²

so 3/5 LW = 42/2*3 = 63 m²

New Area = 63 m²

Original Area = 63/3*5 = 105 m²

Percentage decease in area = 42/105*100 = 40%