Finding the Third Proportional to 390 and 454
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Solution
The third proportional to 390 and 454 is: 528.50
Step by Step Solution
- Step 1: Write the proportion equation
390 : 454 = 454 : x - Step 2: Convert to fraction form
390/454 = 454/x - Step 3: Cross multiply
390x = 454 × 454 - Step 4: Simplify right side
390x = 206,116 - Step 5: Solve for x
x = 206,116/390 - Step 6: Final answer
x = 528.50
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These problems maintain the same ratio (1.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.