Samantha is 1.1 m tall on her eleventh birthday and 1.21 m tall on her twelfth birthday. By what factor has her height increased?

Well to figure this out you can simply get how tall she is now which is 1.21 m tall and subtract how tall she used to be which is 1.1 from that. If you subtract them you should have got 0.11 m making the total that she grew to be 0.11. Hope I Helped.:)