What are the next three numbers in this series? 4, 6, 12, 18, 30, 42, 60, 72, 102, 108,…?

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The numbers have prime numbers before and after them such as, 4 (3 and 5 prime), 6 (5 and 7 prime) and so on to, 108 (107 and 109 prime). So the next three numbers are, 138 (137 and 139 prime), 150 (149 and 151 prime), 180 (179 and 181 prime)

A boy is twice as old as his sister, and half as old as their father. In 50 years, his sister will be half as old as their father. How old is the boy now?

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He is 50 years old.

Can you take 9 from 6, 10 from 9, 50 from 40 and still be left with 6?

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Of course you can,

SIX – 9(IX)=S

9 (IX) – 10 (X) = I

40 (XL) – 50 (L) = X

SIX!

I’m there once in a minute, twice in a moment but never in a thousand years. Who am I?

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The letter M!

How many two cent stamps are there in a dozen?

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12, a dozen of anything is still 12!

There are 10 apples with you, and 10 friends who want them. You give each an apple, yet one apple remains in the basket…how is this possible?

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Well, it’s simple, you give 9 apples to your friends, and the last apple you give to your 10th friend with the basket!

A 40-yard long street has a tree every 10 yards on both sides. How many trees are there?

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10, 5 on either side

A woman has 7 daughters and they each have a brother, how many children does she have?

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8 children, the sisters have just one brother!

A frog fell into a hole that was 14½ feet deep. He could jump 3 feet, but he slid back a foot each time he jumped. How many jumps does it take him to get out of the hole?

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Every 3 feet jump accompanied by a 1 foot slide equals 2 feet high jumps each; at this rate, so the 7th jump, starting at 12 feet, brings him to 15 feet, which takes him out of the hole.