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77julia77
11 days ago
11

A mail clerk found that the total weight of 155 packages was 815 pounds. if each of the packages weighed either 3 pounds or 8 po

unds, how many of the packages weighed 8 pounds?
Mathematics
2 answers:
tester [3.9K]11 days ago
7 0

Answer:

70 packages of 8 pounds each

Step-by-step explanation:

A mail clerk discovered that 155 packages had a total weight of 815 pounds.

The packages weighed either 3 pounds or 8 pounds each.

Let x represent the number of 3-pound packages and y represent the number of 8-pound packages.

The equation for total packages is 155:

So,  x + y = 155 ------(1)

The equation for total weight of the packages is:

3-pound packages total weight = 3x

8-pound packages total weight = 8y

The total weight of all packages = 815:

3x + 8y = 815 -----------(2)

Now solve equations (1) and (2).

Multiply the first equation by -3:

-3x - 3y = -465

Combine with 3x + 8y =  815:

5y = 350.

y = 70

This means there are 70 packages that weigh 8 pounds each.

tester [3.9K]11 days ago
3 0
To solve this problem, you'll need to create two equations:
x + y = 155 (total packages)
3x + 8y = 815 (total weight)
Next, multiply the first equation by 3: 3x + 3y = 465.
Then, subtract the first equation from the second to find that 5y = 350, which means y = 70. Thus, there are 70 packages that weigh 8 pounds. 
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Response:

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Step-by-step explanation:

Given data:

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Required:

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A non-member pays $0.20 per game;

Annual cost can be determined using the formula;

y = Amount * Number of Games

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Amount = $0.2, Number of Games = x

y = 0.20 * x

Convert 0.2 to a fraction:

y = \frac{2}{10} * x

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y = \frac{1}{5}x

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