Given the simple interest formula:
I = P•R•T
where:
I = interest
P = principal
R = interest rate
T = time (in years)
We can isolate R algebraically to find out the interest rate:
I = P•R•T
Divide both sides by P•T:
I / (P•T) = (P•R•T)/(P•T)
The formula for the interest rate is:
R = I / (P•T)
Substitute the given values into this formula to solve for the interest rate (R):
R = I / (P•T)
R = $490/ ($1,400 • 5 years)
R = $490 / $7,000
R = 0.07 or 7%
Therefore, the interest rate is 7%.
Please mark my answers as the Brainliest if you find my explanations and solution helpful :)
Draw a diagram to illustrate the problem as shown in the figure below.
Let h the height of the hill. =
At position A, the angle of elevation is 40°, and the horizontal distance to the foot of the hill is x.
By definition,
tan(40°) = h/x h = x tan40 = 0.8391x
(1)
At position B, Joe is (x - 450) ft from the foot of the hill. His angle of elevation is
40 + 18 = 58°.
By definition, tan(58°) = h/(x - 450)
h = (x - 450) tan(58°) = 1.6003(x-450)
h = 1.6003x - 720.135 (2)
Equate (1) and (2).
1.6003x - 720.135 = 0.8391x 0.7612x = 720.135
x = 946.0523
From (1), obtain
h = 0.8391*946.0523 = 793.8 ft
Answer: The height of the hill is approximately 794 ft (nearest integer)
All you do is subtract the two numbers