Answer:
1.5 hours
Step-by-step explanation:
1/2 + 1/2 + 1/2 =1.5
They were without electricity for 47 minutes.....determine the percent of an hr....so 1 hr = 60 minutes.....so they were out 47 out of 60 minutes...
47/60 = 0.783 = 78.3%.....so just type in 78.3 because ur not supposed to include the percent sign
The first equation given 
We have to add 1 and 5 to the right side first. We will get,

To get rid of 6 from the right side we have to subtract 6 from both sides.



To find n we have to move -2 to the other side by dividing both side by -2.



So we have got the required answer for the first question.
The solution is n = 0.
The second equation given,

First we have to move 7x to the left side by subtracting it from both sides.



Now we have to move -2 to the right side by adding 2 to both sides.



We have got the required answer for the second question.
The solution is x = -7.
The third equation given,

We have to get rid of that negative sign from both sides. As we have negative sign to both sides we can cancel it out. We will get,

Now we have to move 4 to left side by subtracting it from both sides.




So we have got the required answer .
The solution is x = 4.
Multiply by a across the formula