Question

One circle has a radius of 98 cm and a second concentric circle has a radius of 1 m 26 cm how much longer is the circumference of the second circle than that of the first

Answer 1

Radius 1 = 98cm
Radius 2 = 126cm ( 1m = 100cm)

Circumfrence of circle 1 = 2*PIE*R1
→2*22/7*98
→2*22*14 ( 7 AND 98 will cancle each other)
→44*14 = 616cm

Circumfrence or circle 2 = 2*PIE*R2
→2*22/7*126
→2*22*18 ( 7 & 126 will cancle each other)
→44*18 = 792cm

Difference = C2 - C1
→792-616 = 176cm

Answer 2

Given:-One circle has a radius of 98 cm and a second concentric circle has a radius of 1 m26 cm or 126cm

To find out:-How much longer is the circumference of the second circle than that of first?

Solution:-

Let the radius of outer circle be r1 and inner circle be r2 .

CIRCUMFERENCE of inner circle = 2πr1

=>2×22/7×98

=>616 cm

CIRCUMFERENCE of outer circle = 2πr2

=>2×22/7×126

=>792 cm

DIFFERENCE of outer circle and inner circle

=>792-616=176 cm

circumference of the second circle is 176 cm longer than that of first.