Simple...
you have: -7=c-6
You want to isolate the variable c
-7=c-6
-7=c-6
+6 +6
-1=c
Thus, your answer.
From 86 books to 150 books. An increase of 64 books.
(150 - 86) / 86 = 64 / 86 = 0.744 * 100% = 74.40% or 74% increase
150 / 86 = 1.744 * 100% = 174.40%
86 is the basis. It is 100%
If the problem asks for the value of the percentage increase and the rate is given 74.4% of 86. Then 86 * 74.4% = 64. You just add 64 to 86 to get the new total of books which is 150.
12/x+5
x represents “a number” because it’s unknown and the + sign is because the words sum
The answer to the question is 0.44
