Home / 1,288.28-1,931.60-422.40

Finding the Fourth Proportional to 1,288.28, 1,931.60 and 422.40

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Solution

The fourth proportional to 1,288.28, 1,931.60 and 422.40 is: 633.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,288.28 : 1,931.60 = 422.40 : x
  2. Step 2: Convert to fraction form
    1,288.28/1,931.60 = 422.40/x
  3. Step 3: Cross multiply
    1,288.28x = 1,931.60 × 422.40
  4. Step 4: Simplify right side
    1,288.28x = 815,907.84
  5. Step 5: Solve for x
    x = 815,907.84/1,288.28
  6. Step 6: Final answer
    x = 633.33

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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.