If the diameter of a circle with a circumference of 19.5 inches is reduced by three, what would be the circumference of the new circle?

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It is given that the circumference of the circle is 19.5 inches. Let the diameter is d inches .

And the formula of circumference is

[tex]C= \pi d[/tex]

Substituting the value of C, we will get

[tex]19.5= \pi d \\ d = \frac{19.5}{ \pi}[/tex]

When the diameter increased by 3, then the circumference is

[tex]C = \pi ( \frac{19.5}{ \pi} +3})=Approx 29 inches[/tex]

And the circumference , when diameter is increased by 3 is 29 inches .

Since the circumference of a circle = 19.5 inches

[tex]2\Pi r = 19.5[/tex]

[tex]2 \times \frac{22}{7} \times r = 19.5[/tex]

[tex]r = \frac{19.5 \times 7}{22 \times 2}[/tex]

r = 3.1 inches

So, diameter = 2r = [tex]2 \times 3.1 = 6.2[/tex] inches.

Since. the diameter of new circle is reduced by three.

Therefore, D = 6.2-3 = 3.2 inches.

R = 3.2 [tex]\div 2 = 1.6[/tex] inches

Now, circumference of new circle

= [tex]2 \pi r[/tex]

= [tex]2 \times \frac{22}{7} \times 1.6[/tex]

=10 inches

So, the circumference of the new circle is 10 inches.