Peter and his dad Rupert shared the same birthday.  To make it special, they each got their own birthday cake.  Peter has 10 candles on his cake.  Rupert is 3 and 1/2 times older than Peter.  How many candles will be on Rupert's cake?
Peter is 10 years old because he has 10 birthday candles on his cake.
Rupert is 3.5 times older than Peter so Rupert will have 3.5*10 = <<3.5*10=35>>35 candles on his cake.
#### 35