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2 years ago

An air-conditioning company counted 56 invoices at the end of the month. They charge $450 for a new installation and $75

Mathematics

1 answer:

k0ka [10]2 years ago

8 0

Answer:

14 installatons

42 service calls

Step-by-step explanation:

Let x = no. of new installations

y = no. of service calls

(1) x + y = 56 (2) 450x + 75y = 9450

y = 56 - x 450x + 75(56 - x) = 9450

450x + 4200 - 75x = 9450

375x = 5250

x = 14 installatons

y = 56 - 14 = 42 service calls

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What is the dimension of a rectangle if the perimeter is 198

AfilCa [17]

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Length = 49.5 unit and width = 49.5 unit

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2 years ago

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Find the sum of the first 7 terms of the following series, to the nearest integer. 150,60,24...

Sonja [21]

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<h3>What is geometrical series?</h3>

A geometric series is the collection of an unlimited number of terms with a fixed ratio between them.

The given series is an geometric series, the details of the series are:

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Learn more about Geometrical Series:

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