mary decreased her time in the mile walk from 30 minutes to 24 minutes. What was the percent of decrease?

1 answer:

3 0

(24/30)*100 = 80%

Therefore she decreased from 100% to 80%, which is about 20% decrease.
Thus, the answer is 20%

Another way to do this is.

$\frac{(Original value - current value)}{Original value} * 100% = percentage of change in value$

Which in this case is
$\frac{30-24}{30} * 100% = 20%$

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The height of a wooden pole, h, is equal to 15 feet. Ataut wire is stretched from a point on the ground to the top of the pole.

Taya2010 [7]

The question is incomplete. Here is the complete question:

The height of a wooden pole, h, is equal to 15 feet. A taut wire is stretched from a point on the ground to the top of the pole. The distance from the base of the pole to this point on the ground, b. is equal to 8 feet. What is the length of the wire?

Answer:

Length of wire = 17 feet

Step-by-step explanation:

Given:

The height of the wooden pole is, $h=15\ ft$

The distance from the base of the pole to this point on the ground is, $b=8\ ft$

Let the length of the wire be 'l'.

Now, consider the triangle formed by the pole, the base, and the wire. The length of the wire is the slant length and hence the hypotenuse of the triangle.

Using Pythagorean theorem, we can find the hypotenuse.

$(Hypotenuse)^2=(height)^2+(base)^2\\l^2=h^2+b^2$