Finding the Third Proportional to 390 and 501
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Solution
The third proportional to 390 and 501 is: 643.59
Step by Step Solution
- Step 1: Write the proportion equation
390 : 501 = 501 : x - Step 2: Convert to fraction form
390/501 = 501/x - Step 3: Cross multiply
390x = 501 × 501 - Step 4: Simplify right side
390x = 251,001 - Step 5: Solve for x
x = 251,001/390 - Step 6: Final answer
x = 643.59
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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.