Can you very be kind and answer

Mathematics

1 answer:

Lera25 [3.4K]3 years ago

4 0

area of a circle is PI x r^2

2 = d/2 = 5.4/2 = 2.7 cm

using 3.14 for PI

3.14 x 2.7^2 = 22.89 square inches

360 degree in a circle, shaded area is 180 degree, which is 50%

so 22.89 x .5 = 11.45 cm^2

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john is twice as old as mary. the sum of their ages is 21. how old is mary? let j = john's age and m = mary's age. select the sy

Verdich [7]

Hello,

let's assume j the john's age, m the mary's age.

"John is twice as old as mary"==>j=2*m

"the sum of their ages is 21" ==>j+m=21

==>2*m+m=21
==>3m=21
==>m=7
and j=21-7=14

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