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%.
Answer:
IT depends
Step-by-step explanation:
To<span> find a </span>power of a product, look the power of each factor and then multiply. If you want to multiply two powers with the same exponent but different bases, you use the commutative property of multiplication. Product of powers property shows us that when you multiply powers with the same base you just have to add the exponents. This is raising a <span>power to a power.</span>
Answer: Period: 4. Amplitude: 3
Step-by-step explanation: The period is how long it takes for one cycle of the function (one up and down). In this graph, one cycle ends at 4.
The amplitude is how far away the extremes of the graph are from the midline. This graph is a total of 6 units tall, making the amplitude 3. (I usually find total graph height and divide by 2.)
Jason = 142 cm = 1.42 m
Amy = 137 cm = 1.37 m
Joseph = 1397 mm = 1.397 m
From shortest to tallest
I) Amy, Joseph, Jason
