Finding the Third Proportional to 390 and 671.50
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Solution
The third proportional to 390 and 671.50 is: 1,156.19
Step by Step Solution
- Step 1: Write the proportion equation
390 : 671.50 = 671.50 : x - Step 2: Convert to fraction form
390/671.50 = 671.50/x - Step 3: Cross multiply
390x = 671.50 × 671.50 - Step 4: Simplify right side
390x = 450,912.25 - Step 5: Solve for x
x = 450,912.25/390 - Step 6: Final answer
x = 1,156.19
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These problems maintain the same ratio (1.72) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.