Answer:
66
Step-by-step explanation:
Use the formula for the mean of a set of numbers:
sum of the numbers
average = --------------------------------
count of numbers
Here we know that the average mark was 68, so we can write:
75 + 62 + 84 + 53 + x
average = 68 = ----------------------------------
5
or 274 + x
68 = -------------------
5
Solving for x, we multiply both sides by 5: 340 = 274 + x.
Subtracting 274 from both sides effectively isolates x:
340 = 274 + x
- 274 -274
------------------------
66 = x
The fifth student's mark was 66.
Those number are all powers of 10
10= 10^1
100= 10^2
1000= 10^3
and so on...
25/20 × 100% = 125%
125% - 100% = 25%
25% profit :)
Answer:
d is answer i 100% sure for first
I took geometry a while ago, I can help if you want.
