Home / 1,439.36-2,156.88-861.60

Finding the Fourth Proportional to 1,439.36, 2,156.88 and 861.60

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Solution

The fourth proportional to 1,439.36, 2,156.88 and 861.60 is: 1,291.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,439.36 : 2,156.88 = 861.60 : x
  2. Step 2: Convert to fraction form
    1,439.36/2,156.88 = 861.60/x
  3. Step 3: Cross multiply
    1,439.36x = 2,156.88 × 861.60
  4. Step 4: Simplify right side
    1,439.36x = 1,858,367.81
  5. Step 5: Solve for x
    x = 1,858,367.81/1,439.36
  6. Step 6: Final answer
    x = 1,291.11

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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.