Finding the Third Proportional to 390 and 439.50
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Solution
The third proportional to 390 and 439.50 is: 495.28
Step by Step Solution
- Step 1: Write the proportion equation
390 : 439.50 = 439.50 : x - Step 2: Convert to fraction form
390/439.50 = 439.50/x - Step 3: Cross multiply
390x = 439.50 × 439.50 - Step 4: Simplify right side
390x = 193,160.25 - Step 5: Solve for x
x = 193,160.25/390 - Step 6: Final answer
x = 495.28
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These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.