Solve the Nested Division: 2/7 ÷ (3/5 ÷ (7÷8))

Question

27:(35:(7:8))=? \frac{2}{7}:(\frac{3}{5}:(7:8))=\text{?}

Video Solution

Solution Steps

00:00 Solve
00:03 Always solve parentheses first, the rule applies even within parentheses
00:06 Start with the innermost parentheses
00:09 Write division as a fraction
00:14 Division is also multiplication by the reciprocal
00:23 Be sure to multiply numerator by numerator and denominator by denominator
00:31 Division is also multiplication by the reciprocal
00:39 Be sure to multiply numerator by numerator and denominator by denominator
00:45 Reduce what we can
00:52 Break down 8 into factors 2 and 4
00:56 Reduce what we can
01:01 And this is the solution to the question

Step-by-Step Solution

First, we rewrite the multiplication exercise inside parentheses as a fraction:

27:(35:78)= \frac{2}{7}:(\frac{3}{5}:\frac{7}{8})=

Now we invert the fraction to create a multiplication exercise:

27:(35×87)=27:(3×85×7) \frac{2}{7}:(\frac{3}{5}\times\frac{8}{7})=\frac{2}{7}:(\frac{3\times8}{5\times7})

Now we invert the fraction to create a multiplication exercise:

27×5×73×8=2×5×77×3×8 \frac{2}{7}\times\frac{5\times7}{3\times8}=\frac{2\times5\times7}{7\times3\times8}

We simplify the 7 in the numerator and denominator:

2×53×8= \frac{2\times5}{3\times8}=

We break down the 8 into a shorter multiplication exercise:

2×53×2×4= \frac{2\times5}{3\times2\times4}=

We simplify the 2 in the numerator and denominator:

53×4=512 \frac{5}{3\times4}=\frac{5}{12}

Answer

512 \frac{5}{12}