Let 
be the 20 marks of the boys, and 
be the 10 marks of the girls.
We know that the global mean was 70, meaning that
Multiplying both sides by 30 we deduce that the sum of the scores of the whole classroom is
By the same logic, we work with the marks of the boys alone: we know the average:
And we deduce the sum of the marks for the boys:
Which implies that the sum of the marks of the girls is 
And finally, the mean for the girls alone is
5h - 3 = 17
First, substitute h for 4 and the equation becomes 5(4)-3
Then, use PEMDAS (order of operations) to answer.
5 x 4 = 20
20 - 3 = 17
Answer:
B is the area of the base
Step-by-step explanation:
V= 1/3 Bh
V is the volume
B is the area of the base
h is the height of the pyramid
Answer:
It's the first one
Step-by-step explanation:
Because 2M means you are multiplying all the values of M with 2
Answer:
x = 26
Step-by-step explanation:
m<RTS = 4x - 14 (given)
Based on the inscribed angle theorem, the measure of the inscribed angle in a semicircle = right angle (90°)
Therefore,
4x - 14 = 90
4x - 14 + 14 = 90 + 14 (addition property of equality)
4x = 104
4x/4 = 104/4
x = 26
