Home / 1,289.71-1,934.70-640.27

Finding the Fourth Proportional to 1,289.71, 1,934.70 and 640.27

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Solution

The fourth proportional to 1,289.71, 1,934.70 and 640.27 is: 960.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.71 : 1,934.70 = 640.27 : x
  2. Step 2: Convert to fraction form
    1,289.71/1,934.70 = 640.27/x
  3. Step 3: Cross multiply
    1,289.71x = 1,934.70 × 640.27
  4. Step 4: Simplify right side
    1,289.71x = 1,238,730.37
  5. Step 5: Solve for x
    x = 1,238,730.37/1,289.71
  6. Step 6: Final answer
    x = 960.47

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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.