Home / 1,281.31-1,921.61-459.43

Finding the Fourth Proportional to 1,281.31, 1,921.61 and 459.43

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Solution

The fourth proportional to 1,281.31, 1,921.61 and 459.43 is: 689.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.31 : 1,921.61 = 459.43 : x
  2. Step 2: Convert to fraction form
    1,281.31/1,921.61 = 459.43/x
  3. Step 3: Cross multiply
    1,281.31x = 1,921.61 × 459.43
  4. Step 4: Simplify right side
    1,281.31x = 882,841.63
  5. Step 5: Solve for x
    x = 882,841.63/1,281.31
  6. Step 6: Final answer
    x = 689.02

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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.