Finding the Third Proportional to 685 and 1,580.50
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Solution
The third proportional to 685 and 1,580.50 is: 3,646.69
Step by Step Solution
- Step 1: Write the proportion equation
685 : 1,580.50 = 1,580.50 : x - Step 2: Convert to fraction form
685/1,580.50 = 1,580.50/x - Step 3: Cross multiply
685x = 1,580.50 × 1,580.50 - Step 4: Simplify right side
685x = 2,497,980.25 - Step 5: Solve for x
x = 2,497,980.25/685 - Step 6: Final answer
x = 3,646.69
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Why These Related Problems?
These problems maintain the same ratio (2.31) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.