Finding the Third Proportional to 390 and 578
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Solution
The third proportional to 390 and 578 is: 856.63
Step by Step Solution
- Step 1: Write the proportion equation
390 : 578 = 578 : x - Step 2: Convert to fraction form
390/578 = 578/x - Step 3: Cross multiply
390x = 578 × 578 - Step 4: Simplify right side
390x = 334,084 - Step 5: Solve for x
x = 334,084/390 - Step 6: Final answer
x = 856.63
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These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.