Finding the Third Proportional to 820 and 1,287
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Solution
The third proportional to 820 and 1,287 is: 2,019.96
Step by Step Solution
- Step 1: Write the proportion equation
820 : 1,287 = 1,287 : x - Step 2: Convert to fraction form
820/1,287 = 1,287/x - Step 3: Cross multiply
820x = 1,287 × 1,287 - Step 4: Simplify right side
820x = 1,656,369 - Step 5: Solve for x
x = 1,656,369/820 - Step 6: Final answer
x = 2,019.96
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These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.