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1.) Alice's age is am exact multiple of Betty's age. In eight years, they will both be teenagers. How old are they now?

2.) Colin has two teenage sisters, who are not twins. In three years, the ages of both sisters will be exactly divisible by Colin's age. How old are all three now?

1. 10 and 5.
2 Colin is 8, sister 1 is 13, sister 2 is 14.

Thanks for responding. Would you mind explaining how you got those numbers, it still confuses me. THanks

1. Betty has to be at least 5 if she's to be a teenager in eight years. I tried 5 for Betty and 10 for Alice - that lead to Betty being 13 (in eight years) and Alice being 18. I didn't need to try any other ages after that - and those wouldn't work. If Betty was 6 (now), Alice would be 12 - so wouldn't be a teenager in eight years, and the same goes if Betty was any older.

2. Again, I got this from the first number combination I tried. 13 and 14 are the first teenage numbers. I added three to those, giving 16 and 17, and a total of 33. This is divisible only by 11. Taking three away means that Colin is 8 now. I didn't try any other combinations of teenage numbers, so I don't know if there's another answer.

Something just occurred to me, the second one maybe a trick question.

I think the second one may be incorrect. You may have read it wrong. it isn't asking you to combine the two ages of the sisters total, in order to be divisible by Colin. I think it means, in 3 years, there will be two different numbers representing sister ages, and BOTH of those will be divisible by Colins age.

It just occurred to me that it NEVER says in the 2nd problem that AFTER the three years, it never states the sisters will still be teenagers. Does that make it easier to solve?

The teens are 13 and 17 perhaps

In 3 years they will be 16 and 20

Colin will be 2 or 4 then and is therefore -1 or 1 now

etc

Yes, I did wonder about the slight ambiguity in the second question. I had another attempt and came up with Colin being 1 and the sisters being 13 and 17.

PS I don't like numerical problems very much and seldom do them!

LOL, me neither, it was in an crosswword puzzle book. Your answer this time is "correct", but I am wondering if this is an ambiguous question that can have several answers. This answer just happens to be the first "right" answer. I hate vague questions like tthat, feels like an sat test

It is not quite a unique solution as Colin could be a newborn with sisters aged 15 and 18.

How old is a new born baby?