There are twice as many surfers on Malibu beach as in Santa Monica beach. If there are 20 surfers in Santa Monica, calculate the total number of surfers on the two beaches.
If there are 20 surfers at Santa Monica, Malibu beach has twice as many surfers as Santa Monica has 2*20 = 40 surfers.
Together, the two beaches have a total of 40+20 = <<40+20=60>>60 surfers.
#### 60