Finding the Third Proportional to 642 and 1,407
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Solution
The third proportional to 642 and 1,407 is: 3,083.57
Step by Step Solution
- Step 1: Write the proportion equation
642 : 1,407 = 1,407 : x - Step 2: Convert to fraction form
642/1,407 = 1,407/x - Step 3: Cross multiply
642x = 1,407 × 1,407 - Step 4: Simplify right side
642x = 1,979,649 - Step 5: Solve for x
x = 1,979,649/642 - Step 6: Final answer
x = 3,083.57
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These problems maintain the same ratio (2.19) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.