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3 years ago

6

Lana is the oldest of four sisters. Her youngest sister is half her age. The other two sisters are twins $2$ years younger than

Lana. When the four sisters' ages are added together, the result is $45$. If the youngest sister is $n$ years old, what is $n$?

1 answer:

ivanzaharov [21]3 years ago

6 0

N= 7
2n+n+2n-2+2n-2=45
7n-4=45
7n=49
n=7

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Answer:

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Step-by-step explanation:

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substituting value of a in 2a+b=3,

2×(5+3b)+b=3

or, 10+6b+b=3

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or, 7b=-7

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substituting value of b in(i),

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=5+3×(-1)

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(b)
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4 years ago

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The answer to your question is:

Step-by-step explanation:

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3 years ago

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Galina-37 [17]

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