Finding the Third Proportional to 489 and 636.50
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Solution
The third proportional to 489 and 636.50 is: 828.49
Step by Step Solution
- Step 1: Write the proportion equation
489 : 636.50 = 636.50 : x - Step 2: Convert to fraction form
489/636.50 = 636.50/x - Step 3: Cross multiply
489x = 636.50 × 636.50 - Step 4: Simplify right side
489x = 405,132.25 - Step 5: Solve for x
x = 405,132.25/489 - Step 6: Final answer
x = 828.49
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These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.