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.
Answer:
x =27
Step-by-step explanation:
3x - 4y=65
lets substitute the value of y in the equation:
3x -4(4) =65
3x = 65 +16
3x= 81
x= 81/3
x = 27
(24 × 17 × 130\2)
24 × 17 = 408 x 130 = 53,040 / 2 = 26,520
So the volume of this box is
C= 26,520 cm^3