Finding the Third Proportional to 338 and 390
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Solution
The third proportional to 338 and 390 is: 450
Step by Step Solution
- Step 1: Write the proportion equation
338 : 390 = 390 : x - Step 2: Convert to fraction form
338/390 = 390/x - Step 3: Cross multiply
338x = 390 × 390 - Step 4: Simplify right side
338x = 152,100 - Step 5: Solve for x
x = 152,100/338 - Step 6: Final answer
x = 450
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These problems maintain the same ratio (1.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.