Respuesta :

[tex] \frac{3}{8} [/tex] of 80 cards
You can multiply to get the final answer
[tex] \frac{3}{8} [/tex] x 80
(80 and 8 cancels to give 10)
                       ↓
          3 x 10 = 30 cards


The number of cards he swapped
80 x 3/8
30