We want to know whether the water level for the three-month period is greater than or less than the yearly average. We are given a table that shows the water level in inches for three months compared to the yearly average. Let's look at the table!
June
July
August
- 2 18
1 14
- 7/8
We want to compare the change in the water level over the three months to the yearly average. To do so, we can add the change of the water level in June, July and August.
- 2 18+ 1 14+( - 7/8)
Before we can evaluate the sum involving mixed numbers, the mixed numbers must first be rewritten as fractions.
a bc
a* c+b/c
Simplify
- 2 18
- (2* 8+1/8)
- 17/8
1 14
1* 4+1/4
5/4
When adding fractions, they should have the same denominator. In this case, we have three fractions with two different denominators.
- 2 18+ 1 14+( - 7/8) [0.5em]
⇕ [0.5em]
- 17/8+ 5/4+( - 7/8)
Since 8 is a multiple of 4, we can multiply both the numerator and denominator of 54 by 2 to create a common denominator.
Looking at our expression, we can see that the addends have different signs. This means that the sum should have the sign of the fraction with the greater absolute value. We can start by calculating the absolute value of both addends.
|- 24/8|=24/8and|10/8|=10/8
The absolute value of - 248 is greater than the absolute value of 108. Therefore, our sum will be a negative number. Let's evaluate our expression!
