Finding the Fourth Proportional to 81.24, 121.07 and 81.11
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Solution
The fourth proportional to 81.24, 121.07 and 81.11 is: 120.88
Step by Step Solution
- Step 1: Write the proportion equation
81.24 : 121.07 = 81.11 : x - Step 2: Convert to fraction form
81.24/121.07 = 81.11/x - Step 3: Cross multiply
81.24x = 121.07 × 81.11 - Step 4: Simplify right side
81.24x = 9,820.15 - Step 5: Solve for x
x = 9,820.15/81.24 - Step 6: Final answer
x = 120.88
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.