Finding the Fourth Proportional to 81.70, 122.36 and 51.21
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Solution
The fourth proportional to 81.70, 122.36 and 51.21 is: 76.70
Step by Step Solution
- Step 1: Write the proportion equation
81.70 : 122.36 = 51.21 : x - Step 2: Convert to fraction form
81.70/122.36 = 51.21/x - Step 3: Cross multiply
81.70x = 122.36 × 51.21 - Step 4: Simplify right side
81.70x = 6,266.06 - Step 5: Solve for x
x = 6,266.06/81.70 - Step 6: Final answer
x = 76.70
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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.