Finding the Third Proportional to 490 and 638
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Solution
The third proportional to 490 and 638 is: 830.70
Step by Step Solution
- Step 1: Write the proportion equation
490 : 638 = 638 : x - Step 2: Convert to fraction form
490/638 = 638/x - Step 3: Cross multiply
490x = 638 × 638 - Step 4: Simplify right side
490x = 407,044 - Step 5: Solve for x
x = 407,044/490 - Step 6: Final answer
x = 830.70
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Why These Related Problems?
These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.