Answer:
1) 11.581
2) 10.78
3) 14.8
4) 3.5
5) 16.28
6) .64
7) 23.3
8) 1.24
9) 6.53
10) 1.59
11) 8.79
12) 27.7919
Step-by-step explanation:
Ur smarter than u think. ^_^
Answer:
I think that the answer is a
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

Given that a room is shaped like a golden rectangle, and the length is 29 ft with the ratio of golden rectangle being (1+√5):2, thus the width of the room will be:
ratio of golden triangle=(length if the room)/(width of the room)
let the width be x
thus plugging the values in the expression we get:
29/x=(1+√5)/2
solving for x we get:
x/29=2/(1+√5)
thus
x=(29×2)/(1+√5)
answer is:
x=58/(1+√5)
or
byrationalizing the denominator by multiplying both the numerator and the denominator by (1-√5)
58/(1+√5)×(1-√5)/(1-√5)
=[58(1-√5)]/1-5
=(58√5-58)/4
I wanna day, that both are correct because they substituted the same value into both expressions and the results are the same.
Both squares substitute in 6 and both equal -5.