Finding the Third Proportional to 390 and 554.50
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Solution
The third proportional to 390 and 554.50 is: 788.39
Step by Step Solution
- Step 1: Write the proportion equation
390 : 554.50 = 554.50 : x - Step 2: Convert to fraction form
390/554.50 = 554.50/x - Step 3: Cross multiply
390x = 554.50 × 554.50 - Step 4: Simplify right side
390x = 307,470.25 - Step 5: Solve for x
x = 307,470.25/390 - Step 6: Final answer
x = 788.39
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These problems maintain the same ratio (1.42) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.