The area and the amount of gravel are illustrations of proportions.
7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
The given parameters are:

The number of pound for an area of <em>1 square foot </em>is calculated as follows:

So, we have:


Cross multiply

Divide both sides by 36

The area to be covered with 315lb gravel is calculated as follows:

So, we have:


Cross multiply


Divide both sides by 252

Hence, 7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
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brainly.com/question/13114933
Since it starts with 2 envelopes, subtract 2 from 17 to get how many and in all 3 packs.
17 - 2 = 15
Now, we divide that number by 3 to get how many are in each envelope.
15 / 3 = 5
There are 5 envelopes in each pack.
Answer:
what do you need there's no image or question
Answer:
30
Step-by-step explanation: