Finding the Third Proportional to 390 and 424
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Solution
The third proportional to 390 and 424 is: 460.96
Step by Step Solution
- Step 1: Write the proportion equation
390 : 424 = 424 : x - Step 2: Convert to fraction form
390/424 = 424/x - Step 3: Cross multiply
390x = 424 × 424 - Step 4: Simplify right side
390x = 179,776 - Step 5: Solve for x
x = 179,776/390 - Step 6: Final answer
x = 460.96
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These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.