Finding the Third Proportional to 390 and 426
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Solution
The third proportional to 390 and 426 is: 465.32
Step by Step Solution
- Step 1: Write the proportion equation
390 : 426 = 426 : x - Step 2: Convert to fraction form
390/426 = 426/x - Step 3: Cross multiply
390x = 426 × 426 - Step 4: Simplify right side
390x = 181,476 - Step 5: Solve for x
x = 181,476/390 - Step 6: Final answer
x = 465.32
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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.