Finding the Fourth Proportional to 81.21, 112.08 and 52.08
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Solution
The fourth proportional to 81.21, 112.08 and 52.08 is: 71.88
Step by Step Solution
- Step 1: Write the proportion equation
81.21 : 112.08 = 52.08 : x - Step 2: Convert to fraction form
81.21/112.08 = 52.08/x - Step 3: Cross multiply
81.21x = 112.08 × 52.08 - Step 4: Simplify right side
81.21x = 5,837.13 - Step 5: Solve for x
x = 5,837.13/81.21 - Step 6: Final answer
x = 71.88
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.