Finding the Fourth Proportional to 81.22, 121.84 and 27.12
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Solution
The fourth proportional to 81.22, 121.84 and 27.12 is: 40.68
Step by Step Solution
- Step 1: Write the proportion equation
81.22 : 121.84 = 27.12 : x - Step 2: Convert to fraction form
81.22/121.84 = 27.12/x - Step 3: Cross multiply
81.22x = 121.84 × 27.12 - Step 4: Simplify right side
81.22x = 3,304.30 - Step 5: Solve for x
x = 3,304.30/81.22 - Step 6: Final answer
x = 40.68
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.