Home / 1,289.67-1,934.15-640.23

Finding the Fourth Proportional to 1,289.67, 1,934.15 and 640.23

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Solution

The fourth proportional to 1,289.67, 1,934.15 and 640.23 is: 960.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.67 : 1,934.15 = 640.23 : x
  2. Step 2: Convert to fraction form
    1,289.67/1,934.15 = 640.23/x
  3. Step 3: Cross multiply
    1,289.67x = 1,934.15 × 640.23
  4. Step 4: Simplify right side
    1,289.67x = 1,238,297.65
  5. Step 5: Solve for x
    x = 1,238,297.65/1,289.67
  6. Step 6: Final answer
    x = 960.17

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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.