Finding the Fourth Proportional to 679.74, 938.70 and 447
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Solution
The fourth proportional to 679.74, 938.70 and 447 is: 617.29
Step by Step Solution
- Step 1: Write the proportion equation
679.74 : 938.70 = 447 : x - Step 2: Convert to fraction form
679.74/938.70 = 447/x - Step 3: Cross multiply
679.74x = 938.70 × 447 - Step 4: Simplify right side
679.74x = 419,598.90 - Step 5: Solve for x
x = 419,598.90/679.74 - Step 6: Final answer
x = 617.29
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.