Home / 1,398.28-1,929.68-768.86

Finding the Fourth Proportional to 1,398.28, 1,929.68 and 768.86

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Solution

The fourth proportional to 1,398.28, 1,929.68 and 768.86 is: 1,061.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,398.28 : 1,929.68 = 768.86 : x
  2. Step 2: Convert to fraction form
    1,398.28/1,929.68 = 768.86/x
  3. Step 3: Cross multiply
    1,398.28x = 1,929.68 × 768.86
  4. Step 4: Simplify right side
    1,398.28x = 1,483,648.23
  5. Step 5: Solve for x
    x = 1,483,648.23/1,398.28
  6. Step 6: Final answer
    x = 1,061.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.