Answer:
The answer is 7 1/2 or 15/2 or 7.5 (all the same just in mixed fraction and decimal form)
Step-by-step explanation:
Answer
Answer
The speedometer is likely to show the speed is either 36.0 mph or 44.0 mph.
To prove
Formula

Where error = |Approx value - Exact value |
First case
As given
A speedometer has a percent error of 10%. The actual speed of the car is 40 mph.
Here
Percentage error = 10%
Exact value = 40 mph
error = - (Approx value - Exact value )
= - (Approx value - 40 )
= - Approx value + 40
Put in the formula


Thus
Approx value = 40 - 4
Approx value = 36 mph
Therefore Option (b) is correct .
Second Case
error = (Approx value - Exact value )
= (Approx value - 40 )
= Approx value - 40
Put in the formula


Thus
Approx value = 40 + 4
Approx value = 44 mph
Therefore Option (c) is correct .
- 1 < - x/3 < 1
1st. Multiply all parts by 3:
-3 < - 3x/3 < 3. Simplify the mid term:
-3 < -x < 3. Now multiply all terms by - 1. Note when you multiply by a negative number, you flip the inequality signs:
(-1)(-3) < (-1)(-x) < (-1)(3)
+3 > x> -3