Finding the Fourth Proportional to 489, 674.82 and 305
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Solution
The fourth proportional to 489, 674.82 and 305 is: 420.90
Step by Step Solution
- Step 1: Write the proportion equation
489 : 674.82 = 305 : x - Step 2: Convert to fraction form
489/674.82 = 305/x - Step 3: Cross multiply
489x = 674.82 × 305 - Step 4: Simplify right side
489x = 205,820.10 - Step 5: Solve for x
x = 205,820.10/489 - Step 6: Final answer
x = 420.90
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.