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Finding the Fourth Proportional to 1,021.80, 1,531.80 and 611.10

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Solution

The fourth proportional to 1,021.80, 1,531.80 and 611.10 is: 916.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,021.80 : 1,531.80 = 611.10 : x
  2. Step 2: Convert to fraction form
    1,021.80/1,531.80 = 611.10/x
  3. Step 3: Cross multiply
    1,021.80x = 1,531.80 × 611.10
  4. Step 4: Simplify right side
    1,021.80x = 936,082.98
  5. Step 5: Solve for x
    x = 936,082.98/1,021.80
  6. Step 6: Final answer
    x = 916.11

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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.