A plank of wood 4.25 m long and 3.4 m wide is to be cut into square pieces of equal size. How many square pieces of largest size can be cut from the plank, if no wastage is allowed?

Correct option is B

Given:

Length of plank = 4.25 m

Width of plank = 3.4 m

Concept:

To find the largest size of square pieces that can be cut without

wastage, we need to find the greatest common divisor (GCD) of the

length and width of the plank.

Formula Used:

GCD of two numbers a and b is the largest number that divides both a

and b without leaving a remainder.

Solution:

Length = 4.25 m = 425 cm

Width = 3.4 m = 340 cm

GCD(425, 340) = 85 cm

=> Number of pieces along the length = 425 / 85 = 5

=> Number of pieces along the width = 340 / 85 = 4

=> Total number of pieces = 5 × 4 = 20

Hence, the number of square pieces of the largest size that can be cut from the plank is 20.