Answer:
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Step-by-step explanation:
Given
In 1990; Income= $39000
In 2010; Income= $70768
Solving (a): An equation in form of f(x) = ax + b
First, we need to determine the slope, a

Taking y as income and x as year index.
When x = 0; y = 39000
When x = 20; y = 70768
Substitute these values in the above formula



Next, is to determine the formula using:

<em>Considering :When x = 0; y = 39000, we have</em>
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<em>Make y the subject of formula</em>
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<em>Express y as a function of x</em>
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Solving (b): Income in 2005
<em>In 2005, x = 15</em>
So:
becomes


3/4 of 120
=3/4*120
=360/4
=90
3/8 of 160
=3/8*160
=480/8
=60
Answer:
There were 30 questions on the test.
Step-by-step explanation:
1. Set up your equation: 27/90 = y/100
2. Next you want to cross multiply: 2700 = 90y or 270 = 9y
3. Divide 270 by 9 to find your y: y = 30
There were 30 questions on the test.
Answer:

Step-by-step explanation:


Hope it helps you!!
#IndianMurga(. ❛ ᴗ ❛.)