Finding the Third Proportional to 691 and 1,289
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Solution
The third proportional to 691 and 1,289 is: 2,404.52
Step by Step Solution
- Step 1: Write the proportion equation
691 : 1,289 = 1,289 : x - Step 2: Convert to fraction form
691/1,289 = 1,289/x - Step 3: Cross multiply
691x = 1,289 × 1,289 - Step 4: Simplify right side
691x = 1,661,521 - Step 5: Solve for x
x = 1,661,521/691 - Step 6: Final answer
x = 2,404.52
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These problems maintain the same ratio (1.87) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.