Finding the Third Proportional to 392 and 438
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Solution
The third proportional to 392 and 438 is: 489.40
Step by Step Solution
- Step 1: Write the proportion equation
392 : 438 = 438 : x - Step 2: Convert to fraction form
392/438 = 438/x - Step 3: Cross multiply
392x = 438 × 438 - Step 4: Simplify right side
392x = 191,844 - Step 5: Solve for x
x = 191,844/392 - Step 6: Final answer
x = 489.40
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These problems maintain the same ratio (1.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.