Finding the Fourth Proportional to 81.24, 121.70 and 58.36
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Solution
The fourth proportional to 81.24, 121.70 and 58.36 is: 87.43
Step by Step Solution
- Step 1: Write the proportion equation
81.24 : 121.70 = 58.36 : x - Step 2: Convert to fraction form
81.24/121.70 = 58.36/x - Step 3: Cross multiply
81.24x = 121.70 × 58.36 - Step 4: Simplify right side
81.24x = 7,102.41 - Step 5: Solve for x
x = 7,102.41/81.24 - Step 6: Final answer
x = 87.43
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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.