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%.
We will have that for the previous year, he had in the account:

For the year previous to that one, he had:

For the previous year to that, he had:

For the year previous to that one, he had:

For the second year that the money was in the account, there was:

And the orinial ammount of money that was in the account was:

From this, we know that Jhon had originally $1400.37 in the bank account.
First you must multiply the number by the percent. (19*27= 513)
Then you divide the answer by 100, or move decimal two places to the left. (513/100= 5.13)
Then round to the nearest whole number (5.13 is approximately 5)
Therefore 19%of 27 = 5
:)
The answer is 1738
Hope this helps you