Answer:
There are 80 marks in total.
Step-by-step explanation:
Let the number of total marks be
.
The percentage score of the student can be written as the ratio
.
However,
.
Equating the two:
.
Cross-multiply (that is: multiple both sides by
, the product of the two denominators) to get
.
.
In other words, there are 80 marks in total.
n - 4 = 16 Given
+ 4 + 4 Cancel out 4 to isolate n variable
n = 20
Prove.
20 - 4 = 16
16 = 16
True.
Answer:
3.74165738677
Step-by-step explanation:
The main property is as follow
(A^p)^q=A^pxq
so only Sam's work is correct because
(8^4)^5 x(7^3)^9=(8^4x5)x(7^3x9)=8^20x 7^27