Finding the Third Proportional to 405 and 517.50
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Solution
The third proportional to 405 and 517.50 is: 661.25
Step by Step Solution
- Step 1: Write the proportion equation
405 : 517.50 = 517.50 : x - Step 2: Convert to fraction form
405/517.50 = 517.50/x - Step 3: Cross multiply
405x = 517.50 × 517.50 - Step 4: Simplify right side
405x = 267,806.25 - Step 5: Solve for x
x = 267,806.25/405 - Step 6: Final answer
x = 661.25
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Why These Related Problems?
These problems maintain the same ratio (1.28) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.