Question

Find the radius of a circle whose circumference is equal to the sum of the circumferences of two circles of radii 15 cm and 18 cm.
NCERT Class X
Mathematics - Exemplar Problems
Chapter _AREA RELATED TO CIRCLES

Answer 1

hello users..........

given that: circle's circumference is equal to the sum of the circumferences of two circles of radii 15 cm and 18 cm.

now ,
solution:-
we know that
the circumference of circle = 2πr
where r is the radius

now.
the circumference of circle of radius 15 cm = 2π×15= 30π cm
&
the circumference of circle of radius 18cm = 2π×18 = 36π

According to question
the circumference of circle whose radius is r = 30π+36π = 66π

=> 2πr =66π
=> r = 33 answer

⭐✡ hope it helps ⭐✡

Answer 2

Answer:

Step-by-step explanation:

we know that

the circumference of circle = 2πr

where r is the radius

now.

the circumference of circle of radius 15 cm = 2π×15= 30π cm

&

the circumference of circle of radius 18cm = 2π×18 = 36π

According to question

the circumference of circle whose radius is r = 30π+36π = 66π

=> 2πr =66π

=> r = 33 answer