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5 votes
Maria solved the equation -5 1/8 n = -9 3/4. Here answer was n = 1 37/41. She is fairly confindent about her answer, but wants to do a quick check of her solution using estimation.

2 Answers

4 votes

Answer: -5(2) = -10

Explanation:

You wanted a rounded answer so just round the numbers and simplify

Hope this helps!

User Etienne Neveu
by
9.4k points
6 votes

Answer:

Yes, she is correct.

Explanation:

Given equation,


-5(1)/(8)n = -9(3)/(4)


(-5-(1)/(8))n=-9-(3)/(4)


((-40-1)n)/(8)=(-36-3)/(4)


-(41)/(8)n =-(39)/(4)


-41* 4n = -39* 8


\implies n =(39* 2)/(41)=(78)/(41)=1(37)/(41)

By estimation :

Since, 1/8 = 0.125 ≈ 0, while, 3/4 = 0.75 ≈ 1


-5(1)/(8)\approx -5

And,
-9(3)/(4)\approx -10


-5n = -10\implies n =(-10)/(-5)=2

Since,
1(37)/(41) is near to 2.

Hence, she is correct.

User Martin Senne
by
8.2k points