How Old is Granny Puzzle - Solution

The Puzzle:

Tom asked his Granny how old she was. Rather than giving him a straight answer, she replied:

"I have 6 children, and there are 4 years between each one and the next. I had my first child (your Uncle Peter) when I was 19. Now the youngest one (Your Auntie Jane) is 19 herself. That's all I'm telling you!"

How old is Tom's Granny?

Our Solution:

Tom's Granny is 58 years old. Let's see why:

First child born: Granny is 19
Second child born: Granny is 23 (19 + 4)
Third child born: Granny is 27 (23 + 4)
Fourth child born: Granny is 31 (27 + 4)
Fifth child born: Granny is 35 (31 + 4)
Sixth child born: Granny is 39 (35 + 4)
Sixth child is 19: Granny is 58 (39 + 19)

Puzzle Author: Stephen Froggatt

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