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:
A. 83
Step-by-step explanation:
I hope this helps :)
Answer:
A
Step-by-step explanation:
The largest square piece will be the largest factor between 24 and 18. This means the largest number that divides into 24 and 18. This number is 6. So each piece will be 6 inches by 6 inches.
I don’t know sorry I’m on this app because I need help myself
Answer:
384 cm²
Step-by-step explanation:
Since it is a square pyramid, the total surface area of the pyramid is the area of its square base plus the area of its 4 triangular faces.
Area of a triangular face
= ½ ×12 ×10
= 60 cm²
Base area of pyramid
= 12 ×12
= 144 cm²
∴ Surface area of pyramid
= 4(60) +144
= 240 +144
= 384 cm²
