You need to first multiply 100 by 42 then divide by 15
6% increase
To calculate the percentage increase:
First: work out the difference (increase) between the two numbers you are comparing.
Increase = New Number - Original Number
Then: divide the increase by the original number and multiply the answer by 100.
% increase = Increase ÷ Original Number × 100.
If your answer is a negative number, then this is a percentage decrease.
Answer:
12 pens
Step-by-step explanation:
Let the variable that can be used to determine the number of pens that Kamila bought be represented by n.
Price of a notebook = $1.59
Price a pen = $0.29
Total amount spent = $5.07
But,
1.59 + 0.29 n = 5.07
So that,
0.29 n = 5.07 - 1.59
0.29 n = 3.48
n = 
= 12
Therefore, Kamila bought 12 pens.