50 points and brainiest if correct. (Write the answer as an inequality solved for c)

Mathematics

1 answer:

scZoUnD [109]3 years ago

6 0

$20 5*4=20
multiply it

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Help me, please A movie theater decreased the size of its popcorn bags by 10%. If the new popcorn bags hold 18 ounces, how much

Iteru [2.4K]

Movie Theater question:

the numerical value of 10% is 0.1, just as 50% is 0.5. if you multiple 20 by 0.1 you get 2, and subtract 2 from 20 you get 18.
The answer is 20 ounces.

Savings Account question:

if you multiply 0.1 by 220 you will get 10% of 220, then just add that answer to 220. so 0.1 x 220 is 22, 22+220 is 242.
The answer is $242.00

I hope this helps :)

6 0

3 years ago

sarah can complete a project in 90 minutes and her sister betty can complete it in 120 minutes if they both work on the project

alukav5142 [94]

Answer:

It will take them approximately 51.43 minutes to complete the project together

Step-by-step explanation:

This is what is called a "shared job" problem.

The best way to work on them is to start by finding the "portion" of the job done by each of the people in the unit of time.

So, for example, Sarah completes the project in 90 minutes, so in the unit of time (that is 1 minute) she completed 1/90 of the total project

Betty completes the project in 120 minutes, so in the unit of time (1 minute) she completes 1/120 of the total project.

We don't know how long it would take for them to complete the project when working together, so we call that time "x" (our unknown).

Now, when they work together completing the entire job in x minutes, in the unit of time they would have done 1/x of the total project.

In the unite of time, the fraction of the job done together (1/x) should equal the fraction of the job done by Sarah (1/90) plus the fraction of the job done by Betty. This in mathematical form becomes:

$\frac{1}{x} =\frac{1}{90} +\frac{1}{120}\\\frac{1}{x} =\frac{4}{360} +\frac{3}{360}\\\frac{1}{x} =\frac{7}{360} \\x=\frac{360}{7} \\x=51.43\,\,min$