Finding the Third Proportional to 689 and 790
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Solution
The third proportional to 689 and 790 is: 905.81
Step by Step Solution
- Step 1: Write the proportion equation
689 : 790 = 790 : x - Step 2: Convert to fraction form
689/790 = 790/x - Step 3: Cross multiply
689x = 790 × 790 - Step 4: Simplify right side
689x = 624,100 - Step 5: Solve for x
x = 624,100/689 - Step 6: Final answer
x = 905.81
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Why These Related Problems?
These problems maintain the same ratio (1.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.