Question

THE RADII OF TWO CIRCLE ARE 19 cm AND 9 cm .FIND THE RADIUS OF THE CIRCLE WHICH HAS CIRCUMFERENCE EQUAL TO THE SUM OF THE CIRCUM FERENCE OF TWO CIRCLE?

Answer 1

Answer: 28 cm

Step-by-step explanation:

Let name the circle as x.

$r_1=19\\r_2=9$

$C_1=2\pi r_1\\C_1=2*(\pi) *19=119.38\\C_2=2\pi r_2\\C_2=2(\pi )9=56.52$

The given situation says ,

$C_x=C_1+C_2$

$C_x=119.38+56.52\\C_x=175$

$C_x=2\pi r_x\\176=2\pi r_x\\r_x=28$

(all figures are rounded of to get a whole as a solution)

Answer 2

Answer:

radius of first circle = 19 CM

circumference of first circle = 2πr1

radius of second circle = 9cm

circumference of second circle =2πr2

now

circumference of both circle=2πr1+2πr2

= 2π(r1+r2)

=2 ×22/7 (19+9)

=2×22/7 (28)

= 2×22×4

= 176cm

Since circumference of both circle = circumference of bigger circle

2πr = 176cm

2×22/7×r = 176cm

44/7 r =176

r= 176 × 7

—

44

r= 28 cm

Hence the radius of bigger circle= 28cm.

hope it is helpful for u