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3 years ago

Use properties to find the sum or product for 3x78

Mathematics

2 answers:

nalin [4]3 years ago

8 0

3 x 78

= 3 x (70+8)

= 210 + 24

= 234

Brut [27]3 years ago

4 0

$3\times78\\-----------------\\78=70+8\\-------------------\\=3\times(70+8)\\------------------------\\use\ distributive\ property:a(b+c)=ab+ac\\--------------------------\\=3\times(70)+3\times(8)=210+24=\huge\boxed{234}$

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How many hundreds in 43617

Nana76 [90]

There are 436 hundreds in 43617.
You can find this by dividing 43617 by 100 and rounding down to the nearest whole number (note: with this method, you have to round down).

Hope this helps :)

7 0

3 years ago

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LenKa [72]

Sin60 =b/10
√3/2 = b/10
b = √3 / 2 (10)
b = 5√3

d^2 = 10^2 - (5√3)^2
d^2 = 100 - 75
d^2 = 25
d = 5

sin30 = b/a
1/2 = 5√3 / a

a = 5√3 (2)
a = 10√3

c^2 = (10√3)^2 - (5√3)^2
c^2 = 300 - 75
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so
a =10√3, b = 5√3, c = 15,d = 5
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D. last choice

4 0

4 years ago

An appliance manufacturer claims to have developed a compact microwave oven that consumes a mean of no more than 250 W. From pre

melamori03 [73]

Answer:

We conclude that a compact microwave oven consumes a mean of more than 250 W.

Step-by-step explanation:

We are given that an appliance manufacturer claims to have developed a compact microwave oven that consumes a mean of no more than 250 W with a population standard deviation of 15 W.

They take a sample of 20 microwave ovens and find that they consume a mean of 257.3 W.

Let $\mu$ = mean power consumption for microwave ovens.

So, Null Hypothesis, $H_0$ : $\mu$ $\leq$ 250 W {means that a compact microwave oven consumes a mean of no more than 250 W}

Alternate Hypothesis, $H_A$ : $\mu$ > 250 W {means that a compact microwave oven consumes a mean of more than 250 W}

The test statistics that would be used here One-sample z test statistics as we know about the population standard deviation;

T.S. = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\bar X$ = sample mean power consumption for ovens = 257.3 W

σ = population standard deviation = 15 W

n = sample of microwave ovens = 20

So, the test statistics = $\frac{257.3-250}{\frac{15}{\sqrt{20} } }$

= 2.176

The value of z test statistics is 2.176.

Now, at 0.05 significance level the z table gives critical value of 1.645 for right-tailed test.

Since our test statistic is more than the critical value of t as 2.176 > 1.645, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that a compact microwave oven consumes a mean of more than 250 W.

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3 years ago

A caterpillar eats 75 leaves in 5 hours. How many leaves will the caterpillar eat in 8 hours if it continues to eat at the same

Dahasolnce [82]

Answer:

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Step-by-step explanation:

If the caterpillar eats 75 leaves in 5 hours and continues to eat at the same rate, the number of leaves eaten is simple, 120 leaves.

How I found the answer:

First, I divided 75 by 5 and got 15, then I multiplied 8 to 15 and got 120.

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Answer:

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Step-by-step explanation:

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