Question

The radii of two circles are 19 cm and 9 cm respectively.

Find the radius of the circle which has circumference equal

to the sum of the circumferences of the two circles.​

Answer 1

Answer:

answer 176

Step-by-step explanation:

first add both radius 19+9=28 now take circumference of circle 2 pie r where pie = 22upon 7 r = 28 now 2 into 7/22 into 28 which give you the

Answer 2

Given : Radii of two circles are 19cm and 9cm respectively.

To Find : Radius of the circle which has circumference equal to the sum of the circumferences of the two circles.

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Let

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• Radius of first circle = R1
• Radius of second circle = R2
• Radius of largest circle = R

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As we know that :

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$\underline{\boxed{\tt\purple{\bigstar \: circumference \: of \: a \: circle \: = 2\pi \: r}}}$

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Firstly we'll find the sum of circumferences of two circles.

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Put the values -

$\tt:\implies \: sum \: of \: circumference = 2\pi(R1 + R2) \\ \\ \\ \tt:\implies \: sum \: of \: circumference = 2\pi(19 + 9) \\ \\ \\ \tt:\implies \: sum \: of \: circumference = 2\pi(28) \\ \\ \\ \tt:\implies \: sum \: of \: circumference \: = 2 \times \frac{22}{\cancel{7}} \times \cancel{28} \\ \\ \\ \tt:\implies \: sum \: of \: circumference \: = \underline{\boxed{\sf\purple{176cm}}} \bigstar$

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Now, we'll find the circumference of the largest circle.

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$\tt:\implies \: circumference \: of \: the \: largest \: circle \: = 2\pi \: R \\ \\ \\ \tt:\implies \: 176 = 2\pi \: R \\ \\ \\ \tt:\implies \: \cancel \frac{176}{2} = \pi \: R \\ \\ \\ \tt:\implies \: 88 = \frac{22}{7} R \\ \\ \\ \tt:\implies \: R \: = \frac{\cancel88 \times 7}{\cancel22} \\ \\ \\ \tt:\implies \: R \: = 7 \times 4 \\ \\ \\ \tt:\implies \: R = \underline{\boxed{\tt\purple{28cm}}} \bigstar \\ \\ \\ \\ \sf\therefore{\underline{Hence, \: the \: radius \: of \: the \: largest \: circle \: i \: \bold{28cm}.}}$