Finding the Fourth Proportional to 81.36, 122.05 and 25.79
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Solution
The fourth proportional to 81.36, 122.05 and 25.79 is: 38.68
Step by Step Solution
- Step 1: Write the proportion equation
81.36 : 122.05 = 25.79 : x - Step 2: Convert to fraction form
81.36/122.05 = 25.79/x - Step 3: Cross multiply
81.36x = 122.05 × 25.79 - Step 4: Simplify right side
81.36x = 3,147.24 - Step 5: Solve for x
x = 3,147.24/81.36 - Step 6: Final answer
x = 38.68
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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.