Home / 1,239.31-1,860.42-979.50

Finding the Fourth Proportional to 1,239.31, 1,860.42 and 979.50

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Solution

The fourth proportional to 1,239.31, 1,860.42 and 979.50 is: 1,470.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,239.31 : 1,860.42 = 979.50 : x
  2. Step 2: Convert to fraction form
    1,239.31/1,860.42 = 979.50/x
  3. Step 3: Cross multiply
    1,239.31x = 1,860.42 × 979.50
  4. Step 4: Simplify right side
    1,239.31x = 1,822,281.39
  5. Step 5: Solve for x
    x = 1,822,281.39/1,239.31
  6. Step 6: Final answer
    x = 1,470.40

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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.