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: y = (x + 5)² + 8
<u>Step-by-step explanation:</u>
y = x²
left 5 units: y = (x + 5)²
up 8 units: y = (x + 5)² + 8
Answer:
Ashely had 30 kisses! Muah!
Step-by-step explanation:
Ratio of Ashely to Keely is 5 : 2 and we know Keely had 12. Keely represents the 2 in this ratio, and how do we get from 2 to 12? We multiply by 6. We have to multiply by 6 on the other side too then. 5 times 6 is 30, so Ashely had 30 hershey kisses.
In real life, not in ratio form, Ashely had 30 kisses and Keely had 12.
Please mark brainliest if possible, have a nice day! :)
Answer:
The probability that a randomly chosen Ford truck runs out of gas before it has gone 325 miles is 0.0062.
Step-by-step explanation:
Let <em>X</em> = the number of miles Ford trucks can go on one tank of gas.
The random variable <em>X</em> is normally distributed with mean, <em>μ</em> = 350 miles and standard deviation, <em>σ</em> = 10 miles.
If the Ford truck runs out of gas before it has gone 325 miles it implies that the truck has traveled less than 325 miles.
Compute the value of P (X < 325) as follows:

Thus, the probability that a randomly chosen Ford truck runs out of gas before it has gone 325 miles is 0.0062.
Answer:
y=1/4x-3/4
Step-by-step explanation:
y=mx+b
m=1/4
b=-3/4