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3 years ago

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An alloy is composed of nickel, zinc, and copper in a 7:2:9 ratio. How many kilograms of each metal is needed to make 3.8 kg of

this alloy?

1 answer:

Tamiku [17]3 years ago

6 0

Ni : Zn: Cu = 7:2:9 =7x : 2x : 9x

7x+2x+9x = 3.8
18x=3.8
x=3.8/18=1.9/9≈0.21

Ni: 7x=7*0.21=1.47 ≈1.5 kg
Zn: 2x=2*0.21=0.42≈0.4 kg
Cu: 9x=9*0.21=1.89 ≈1.9 kg

Check 1.5+0.4+1.9 =3.8 True

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Complete Question

The complete question is shown on the first uploaded image

Answer:

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Step-by-step explanation:

From the question we are told that

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Answer:

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Step-by-step explanation:

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Required

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3 years ago

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Answer:

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III. This finding is significant for a one-tailed test at .01.

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III. This finding is significant for a one-tailed test at .01.

Since the $p_v >\alpha$ . We FAIL to reject the null hypothesis so we have a significant result. TRUE.

So then the correct options is:

d. II and III only

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3 years ago