Finding the Third Proportional to 643 and 1,139
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Solution
The third proportional to 643 and 1,139 is: 2,017.61
Step by Step Solution
- Step 1: Write the proportion equation
643 : 1,139 = 1,139 : x - Step 2: Convert to fraction form
643/1,139 = 1,139/x - Step 3: Cross multiply
643x = 1,139 × 1,139 - Step 4: Simplify right side
643x = 1,297,321 - Step 5: Solve for x
x = 1,297,321/643 - Step 6: Final answer
x = 2,017.61
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These problems maintain the same ratio (1.77) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.