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2 years ago

5

Bobby knows that the perimeter of the original rectangle is 120 meters. He also knows that the perimeter of the reduced rectangl

e is 30 meters and the reduced length is 9 meters. A small rectangle has a length of 9 meters. A larger rectangle is blank. Not drawn to scale What is the width of the original rectangle? 20 meters 24 meters 36 meters 48 meters

2 answers:

Reika [66]2 years ago

7 0

Answer:

b 24 meters

Step-by-step explanation:

ed

Whitepunk [10]2 years ago

6 0

Answer:

<u>24 meters</u> is the width of the original rectangle.

Step-by-step explanation:

Given:

Bobby knows that the perimeter of the original rectangle is 120 meters. He also knows that the perimeter of the reduced rectangle is 30 meters and the reduced rectangle has a length of 9 meters.

Now, to get the width of original rectangle.

The reduced rectangle's perimeter = 30 meters.

The reduced rectangle's length = 9 meters.

Now, we find the width of reduced rectangle by using formula:

Let the width of reduced rectangle be $x.$

$Perimeter=2\times length+2\times width$

$30=2\times 9+2\times x$

$30=18+2x$

<em>Subtracting both sides by 18 we get:</em>

<em /> $12=2x$ <em />

<em>Dividing both sides by 2 we get:</em>

$6=x\\\\x=6\ meters.$

The width of reduced rectangle = 6 meters.

Now, to get the width of original rectangle:

Let the width of original rectangle be $w.$

<em>As given, the perimeter of the original rectangle = 120 meters.</em>

<em>And, the perimeter of reduced rectangle is 30 meters and its width is 6 meters.</em>

<em>So, 30 is equivalent to 6.</em>

<em>Thus, 120 is equivalent to </em> $w.$ <em />

Now, to get the width using cross multiplication method:

$\frac{30}{6}=\frac{120}{w}$

<em>By cross multiplying we get:</em>

<em /> $30w=720$ <em />

<em>Dividing both sides by 30 we get:</em>

<em /> $w=24\ meters.$ <em />

<em>The width of original rectangle = 24 meters.</em>

Therefore, 24 meters is the width of the original rectangle.

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Answer:

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Step-by-step explanation:

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1 year ago

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2 years ago

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Complete options are;

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Answer:

Option C is false

Step-by-step explanation:

Looking at the options,

In normal approximation to the binomial,

n is the sample size,

p is the given probability.

q = 1 - p

Now, one of the conditions for using normal approximation to the binomial is that; np and nq or n(1 - p) must be greater than 10.

This means that option A is true because we require np or n(1 - p) to be greater than 10.

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