Finding the Third Proportional to 421 and 455
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Solution
The third proportional to 421 and 455 is: 491.75
Step by Step Solution
- Step 1: Write the proportion equation
421 : 455 = 455 : x - Step 2: Convert to fraction form
421/455 = 455/x - Step 3: Cross multiply
421x = 455 × 455 - Step 4: Simplify right side
421x = 207,025 - Step 5: Solve for x
x = 207,025/421 - Step 6: Final answer
x = 491.75
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Why These Related Problems?
These problems maintain the same ratio (1.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.