Home / 1,287.88-1,931.85-507.85

Finding the Fourth Proportional to 1,287.88, 1,931.85 and 507.85

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Solution

The fourth proportional to 1,287.88, 1,931.85 and 507.85 is: 761.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.88 : 1,931.85 = 507.85 : x
  2. Step 2: Convert to fraction form
    1,287.88/1,931.85 = 507.85/x
  3. Step 3: Cross multiply
    1,287.88x = 1,931.85 × 507.85
  4. Step 4: Simplify right side
    1,287.88x = 981,085.19
  5. Step 5: Solve for x
    x = 981,085.19/1,287.88
  6. Step 6: Final answer
    x = 761.78

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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.