Answer:
n=5
Step-by-step explanation:
4 + 7n - 42 = -3
+42 +42
4 + 7n = 39
-4 -4
7n = 35
÷7 ÷7
n = 5
To find this answer, we should subtract 2 1/2 from 3 1/4. The simplest way to do this is to turn them into improper fractions, found the least common denominator, and subtract the numerators.
3 1/4=13/4
2 1/2=5/2
The least common multiple is 4, so we should multiply the numerator and denominator of 5/2 by 2.
5/2=10/4
Now we can just subtract the numerators.
13/4-10/4=3/4
Using the math above, we can see that it saves D. 3/4 hours.
7x + 12 = 12
-12 -12
subtract 12 from both sides of the equation as seen above
7x = 0
divide both sides by 7 to isolate the variable
x = 0
B is the correct option.