Finding the Third Proportional to 339 and 639
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Solution
The third proportional to 339 and 639 is: 1,204.49
Step by Step Solution
- Step 1: Write the proportion equation
339 : 639 = 639 : x - Step 2: Convert to fraction form
339/639 = 639/x - Step 3: Cross multiply
339x = 639 × 639 - Step 4: Simplify right side
339x = 408,321 - Step 5: Solve for x
x = 408,321/339 - Step 6: Final answer
x = 1,204.49
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Why These Related Problems?
These problems maintain the same ratio (1.88) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.