Finding the Third Proportional to 642 and 697.50
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Solution
The third proportional to 642 and 697.50 is: 757.80
Step by Step Solution
- Step 1: Write the proportion equation
642 : 697.50 = 697.50 : x - Step 2: Convert to fraction form
642/697.50 = 697.50/x - Step 3: Cross multiply
642x = 697.50 × 697.50 - Step 4: Simplify right side
642x = 486,506.25 - Step 5: Solve for x
x = 486,506.25/642 - Step 6: Final answer
x = 757.80
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These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.