Home / 1,289.28-1,934.08-640.32

Finding the Fourth Proportional to 1,289.28, 1,934.08 and 640.32

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Solution

The fourth proportional to 1,289.28, 1,934.08 and 640.32 is: 960.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.28 : 1,934.08 = 640.32 : x
  2. Step 2: Convert to fraction form
    1,289.28/1,934.08 = 640.32/x
  3. Step 3: Cross multiply
    1,289.28x = 1,934.08 × 640.32
  4. Step 4: Simplify right side
    1,289.28x = 1,238,430.11
  5. Step 5: Solve for x
    x = 1,238,430.11/1,289.28
  6. Step 6: Final answer
    x = 960.56

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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.