Finding the Fourth Proportional to 990.42, 1,484 and 579.90
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Solution
The fourth proportional to 990.42, 1,484 and 579.90 is: 868.90
Step by Step Solution
- Step 1: Write the proportion equation
990.42 : 1,484 = 579.90 : x - Step 2: Convert to fraction form
990.42/1,484 = 579.90/x - Step 3: Cross multiply
990.42x = 1,484 × 579.90 - Step 4: Simplify right side
990.42x = 860,571.60 - Step 5: Solve for x
x = 860,571.60/990.42 - Step 6: Final answer
x = 868.90
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.