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%.
_____
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%.
Answer:
area if square or area of ellipse
Step-by-step explanation:
I think so if I get it word don't get made at me
<span>The inner core is made of solid iron, and it is surrounded by the liquid iron of the outer core. It is solid because the extreme pressure at the center of the earth prevents it from melting, despite the unimaginable temperatures.</span>
Divide the number of fast balls by the total number of pitches:
240 / 384 = 0.625
Answer:
D.
Step-by-step explanation:
The last option, 1.2, cannot represent the probability of an event happening since it is more than 100% (120%). And event cannot have a higher probability of happening than "happening".
A. 0.33 is a valid response, since it represents 33%.
B. 56% is also a valid response.
C. 7/8 is also a valid response since it represents 0,875 or 87,5%.
Hope it helped,
BiologiaMagister
