What is the fastest way to solve this?
\(\dfrac{(0.513)(0.488)(0.942)}{(0.684)(0.314)(0.183)}\)
a) 4
b) 5
c) 6
d) 7
e) 8
Answer: C
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What is the fastest way to solve this?
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regor60
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Try rounding.
First term down to 1/2. Second term up to 1/2, third term up to 1. Adjusted numerator of 1/4.
Adjust first term in denominator down to 2/3, second term up to 1/3, third term up to 1/5. Revised denominator of 2/45.
Notice that this revises terms up and down an equal number of times between numerator and denominator which helps offset estimation errors.
New fraction of (1/4)/(2/45) =45/8. 45/8 is closer to 48/8 than it is to 40/8.
48/8 =6,C
First term down to 1/2. Second term up to 1/2, third term up to 1. Adjusted numerator of 1/4.
Adjust first term in denominator down to 2/3, second term up to 1/3, third term up to 1/5. Revised denominator of 2/45.
Notice that this revises terms up and down an equal number of times between numerator and denominator which helps offset estimation errors.
New fraction of (1/4)/(2/45) =45/8. 45/8 is closer to 48/8 than it is to 40/8.
48/8 =6,C
