Answer:
86%
Step-by-step explanation:
Let g represent the mean mark for the 10 girls in the class. Then the mean mark for the class was ...
10g +20(62%) = 30(70%)
g = 3(.7) -2(.62) . . . . . . . . . divide by 10 and subtract 2(.62)
g = .86 = 86%
The mean mark for girls was 86%.
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You can do this in your head if you consider it in terms of deviations from the mean. The second equation above can be rewritten and factored as ...
g = 70% +2(70% -62%)
That is, because there are 2 boys for every girl, the girl's score is above the mean by an amount that is 2 times the amount that the boy's score is below the mean. The boys' score is below by 8%, so the girls' score is above by 16%, so is 86%.
Largest to Smallest:-
First lets write all the numbers down. 45, 94, 85, 490, 85, 93, 85, 035, 85.
035 is 35.
So lets order them now.
The biggest number is 490 and smallest is 35 (035).
490 - 94 - 93 - 85 - 85 - 85 - 85 - 035 (35)
Answer:
x = 20
Step-by-step explanation:
These angles are equal to each other because they are vertical angles.
Hence, we can equal the two measurements together to solve for x:
3x + 50 = 6x - 10
3x + 60 = 6x
60 = 3x
20 = x
Check your work:
3(20) + 50 = 6(20) - 10
60 + 50 = 120 - 10
110 = 110
Correct
Subtract the number she completed from what she had left to paint originally.
The fractions have different denominators so first step is to rewrite the fractions with a common denominator.
23/25 can be rewritten as 92/100
Now you have 78 21/100 - 34 92/100
Because 21/100 is smaller than 92/100 subtract 1 whole number from 78 and rewrite 1 as 100/100 and add that to the fraction.
78 21/100 becomes 77 121/100
Now subtract :
77 121/100 - 34 92/100
77-34 = 43
And 121/100 - 92/100 = 29/100
Combine to get 43 and 29/100
The answer is 96, don't ask how, just know.
