Proportions with real world problems help, please?

Question

2. A memory card manufacturing facility estimates that four out of 500 cards are faulty. About how many faulty memory cards can be expected for every 1,200 that are manufactured?

 a) set up a proportion, defining a variable for the unknown quantity,

b) solve the proportion, showing all work leading to your answer

c) write a sentence to explain the meaning of the answer for the situation.

Answer 1

(2)

Step 1:

Four out of 500 memory cards are faulty.

Set up a proportion.

Let represent the faulty memory cards among 1200 memory cards.

The proportion is .

Step 2:

Find the number of faulty memory cards among 1200 memory cards.

Use proportions to find .

Therefore, there are approximately 10 faulty memory cards among 1200 memory cards.

Solution:

(a) The proportions is .

(b) .

(c) There are approximately 10 faulty memory cards among 1200 memory cards.