Respuesta :

Answer:

9 pizzas

Step-by-step explanation:

We can use ratios to solve

6/7               x pizza

------------  = ------------

2/21 hour         1 hour

Using cross products

6/7 *1 = 2/21 x

Multiply each side by 21/2

6/7 * 21/2 = x

Rewriting

6/2 * 21/7 =x

3 *3 =x

9

9 pizzas