Answer:
2/11
Step-by-step explanation:
Let's say our fraction is x = 0.1818181818...
The trick is to multiply x by 10²=100 in this case, since there are two repeating digits, and then subtract the original x.
So, in fact you are subtracting 0.181818 from 18.181818 which effectively cancels the entire bit after the decimal point.
You get:
100x - x = 18
Which you can solve:
99x = 18
x = 18/99 = 2/11
Answer: see below
Step-by-step explanation:
3x-12=7x+8 ⇔ given
-12=4x+8 ⇔ addition property of equality
-20=4x ⇔ subtraction property of equality
x=-5 ⇔ division property of equality
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5(x-1)=4x+13 ⇔ given
5x-5=4x+13 ⇔ distributive property
x-5=13 ⇔ subtraction property of equality
x=18 ⇔ addition property of equality
Answer:
23.49
Step-by-step explanation:
Answer: the interval of heights that represents the middle 95% of male heights from this school is between 66 inches and 76 inches.
Step-by-step explanation:
Let x be a random variable representing the heights of males from this school. With the mean and standard deviation given, then the Empirical Rule says the that
1) About 68% of the x values lie between 1 standard deviation below and above the mean.
2) About 95% of the x values lie between 2 standard deviations below and above the mean.
3) About 99.7% of the x values lie between 3 standard deviations below and above the mean.
From the information given,
mean = 71 inches
Standard deviation = 2.5 inches
We want to determine where 95% of x values lies. This is 2 standard deviations from the mean Therefore,
2 standard deviations = 2 × 2.5 = 5 inches
The heights are
71 - 5 = 66 inches and
71 + 5 = 76 inches
