Asmart phone manufacturer uses 10 ounces of gold circuitry to make 5,200 smart phones. if they made 7,800 smart phones last month and gold is valued at $1,300 per ounce, what is the value of gold used last month? a) $19,500 b) $20,500 c) $21,500 d) $22,500

Option A. $19,500

Step-by-step explanation:

A smart phone manufacturer uses 10 ounces of gold circuitry to make 5,200 smartphones.

We will solve this problem by unitary method.

In 5200 smartphones use of gold = 10 ounces

in 1 smartphone use of gold = = 0.001923 ounces

In 7,800 smartphones, use of gold = 0.001923 × 7800 = 14.999 ounces rounded to 15 ounces of gold

Last month the value of 1 ounce gold is $1,300

The value of 15 ounces = 1,300 × 15 =  $19,500

The value of gold used last month is $19,500.

the answer is d

step-by-step explanation: