Finding the Fourth Proportional to 81.79, 122.87 and 70.99
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Solution
The fourth proportional to 81.79, 122.87 and 70.99 is: 106.65
Step by Step Solution
- Step 1: Write the proportion equation
81.79 : 122.87 = 70.99 : x - Step 2: Convert to fraction form
81.79/122.87 = 70.99/x - Step 3: Cross multiply
81.79x = 122.87 × 70.99 - Step 4: Simplify right side
81.79x = 8,722.54 - Step 5: Solve for x
x = 8,722.54/81.79 - Step 6: Final answer
x = 106.65
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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.