Finding the Third Proportional to 990 and 1,261
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Solution
The third proportional to 990 and 1,261 is: 1,606.18
Step by Step Solution
- Step 1: Write the proportion equation
990 : 1,261 = 1,261 : x - Step 2: Convert to fraction form
990/1,261 = 1,261/x - Step 3: Cross multiply
990x = 1,261 × 1,261 - Step 4: Simplify right side
990x = 1,590,121 - Step 5: Solve for x
x = 1,590,121/990 - Step 6: Final answer
x = 1,606.18
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Why These Related Problems?
These problems maintain the same ratio (1.27) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.