Finding the Third Proportional to 642 and 660
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Solution
The third proportional to 642 and 660 is: 678.50
Step by Step Solution
- Step 1: Write the proportion equation
642 : 660 = 660 : x - Step 2: Convert to fraction form
642/660 = 660/x - Step 3: Cross multiply
642x = 660 × 660 - Step 4: Simplify right side
642x = 435,600 - Step 5: Solve for x
x = 435,600/642 - Step 6: Final answer
x = 678.50
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Why These Related Problems?
These problems maintain the same ratio (1.03) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.