Finding the Fourth Proportional to 81.19, 122.09 and 72.08
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Solution
The fourth proportional to 81.19, 122.09 and 72.08 is: 108.39
Step by Step Solution
- Step 1: Write the proportion equation
81.19 : 122.09 = 72.08 : x - Step 2: Convert to fraction form
81.19/122.09 = 72.08/x - Step 3: Cross multiply
81.19x = 122.09 × 72.08 - Step 4: Simplify right side
81.19x = 8,800.25 - Step 5: Solve for x
x = 8,800.25/81.19 - Step 6: Final answer
x = 108.39
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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.