Home / 1,281.78-1,922.87-459.89

Finding the Fourth Proportional to 1,281.78, 1,922.87 and 459.89

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Solution

The fourth proportional to 1,281.78, 1,922.87 and 459.89 is: 689.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.78 : 1,922.87 = 459.89 : x
  2. Step 2: Convert to fraction form
    1,281.78/1,922.87 = 459.89/x
  3. Step 3: Cross multiply
    1,281.78x = 1,922.87 × 459.89
  4. Step 4: Simplify right side
    1,281.78x = 884,296.77
  5. Step 5: Solve for x
    x = 884,296.77/1,281.78
  6. Step 6: Final answer
    x = 689.90

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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.