Finding the Fourth Proportional to 990.12, 1,485.30 and 477
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Solution
The fourth proportional to 990.12, 1,485.30 and 477 is: 715.56
Step by Step Solution
- Step 1: Write the proportion equation
990.12 : 1,485.30 = 477 : x - Step 2: Convert to fraction form
990.12/1,485.30 = 477/x - Step 3: Cross multiply
990.12x = 1,485.30 × 477 - Step 4: Simplify right side
990.12x = 708,488.10 - Step 5: Solve for x
x = 708,488.10/990.12 - Step 6: Final answer
x = 715.56
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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.