If the problem looks like mine, the answer is 152.
The mean = 2,000
s = Sigma ( standard deviation ) = 300
M - 2 s = 2,000- 2 * 300 = 2,000 - 600 = 1,400
M + 2 s = 2,000 + 2 * 300 = 2,000 + 600 = 2,600
Answer.
Useful life of light bulbs within 2 standard deviations of the mean is:
A ) Between 1,400 and 2,600 hours
I divided 5 by 9 and multiplied it by 100 to get the percentage for the probability the horse will win. I got 55.55%. I subtracted 55.55 from 100 and got 44.45% chance of not winning the race.
2c + b = 37 ....multiply by -3
4c + 3b = 81
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-6c - 3b = - 111 (result of multiplying by -3)
4c + 3b = 81
------------------add
-2c = - 30
c = -30/-2
c = 15 <== $ 15 for a can of paint
and it costs $ 7 for each brush
The units digit of a two digit number is 1 less than 3 times the tens digit. if the digits are reversed, the new number is 45 more than the original number. find the number
