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3 years ago

Q7.

Mathematics

1 answer:

VLD [36.1K]3 years ago

3 0

Answer:

Step-by-step explanation:

Let c = sum of ages of all children.

mean age of all children = c/15 = 7

c = 15 * 7 = 105

The sum of the ages of all children is 105.

Let b = sum of ages of the 9 boys.

mean age of boys = b/9 = 5

b = 9 * 5 = 45

The sum of the ages of the boys is 45.

The sum of the ages of the girls is c - b.

c - b = 105 - 45 = 60

The number of girls is 15 - 9 = 6

mean age of girls = (sum of ages of the girls)/(number of girls) =

= 60/6 = 10

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Step-by-step explanation:

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Answer:

If the octagon is clockwise, then after 5 times 45 increments A' will coincide with F.

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Step-by-step explanation:

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It is given that a regular octagon ABCDEFGH rotates 360 degree clockwise about it's center.

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