Finding the Fourth Proportional to 81.18, 121.80 and 27.09
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Solution
The fourth proportional to 81.18, 121.80 and 27.09 is: 40.65
Step by Step Solution
- Step 1: Write the proportion equation
81.18 : 121.80 = 27.09 : x - Step 2: Convert to fraction form
81.18/121.80 = 27.09/x - Step 3: Cross multiply
81.18x = 121.80 × 27.09 - Step 4: Simplify right side
81.18x = 3,299.56 - Step 5: Solve for x
x = 3,299.56/81.18 - Step 6: Final answer
x = 40.65
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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.