A pizza shop tried 45 new type pizza during the past year and 20% percent of them became popular. Which best represents the fraction of pizzas that did not become popular?

To find the fraction of pizzas that did not become popular, we need to first determine the number of pizzas that became popular and then subtract it from the total number of pizzas tried.

Step 1: Calculate the number of pizzas that became popular.
To find 20% of the total number of pizzas, we need to multiply the total number of pizzas by 20% (or 0.20 in decimal form).

20% of 45 pizzas = 0.20 * 45 = 9 pizzas.

Step 2: Calculate the number of pizzas that did not become popular.
To find the number of pizzas that did not become popular, subtract the number of pizzas that became popular from the total number of pizzas.

Total number of pizzas - Pizzas that became popular = Pizzas that did not become popular
45 - 9 = 36 pizzas.

Step 3: Express the fraction of pizzas that did not become popular.
To express it as a fraction, write the number of pizzas that did not become popular over the total number of pizzas.

Fraction of pizzas that did not become popular = 36/45.

So, the fraction that best represents the pizzas that did not become popular is 36/45.