Home / 1,398.41-1,929.80-768.95

Finding the Fourth Proportional to 1,398.41, 1,929.80 and 768.95

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Solution

The fourth proportional to 1,398.41, 1,929.80 and 768.95 is: 1,061.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,398.41 : 1,929.80 = 768.95 : x
  2. Step 2: Convert to fraction form
    1,398.41/1,929.80 = 768.95/x
  3. Step 3: Cross multiply
    1,398.41x = 1,929.80 × 768.95
  4. Step 4: Simplify right side
    1,398.41x = 1,483,915.87
  5. Step 5: Solve for x
    x = 1,483,915.87/1,398.41
  6. Step 6: Final answer
    x = 1,061.15

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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.