Finding the Fourth Proportional to 77.70, 115.91 and 68.70
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Solution
The fourth proportional to 77.70, 115.91 and 68.70 is: 102.49
Step by Step Solution
- Step 1: Write the proportion equation
77.70 : 115.91 = 68.70 : x - Step 2: Convert to fraction form
77.70/115.91 = 68.70/x - Step 3: Cross multiply
77.70x = 115.91 × 68.70 - Step 4: Simplify right side
77.70x = 7,963.19 - Step 5: Solve for x
x = 7,963.19/77.70 - Step 6: Final answer
x = 102.49
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.