Home / 1,286.10-1,929.17-312.21

Finding the Fourth Proportional to 1,286.10, 1,929.17 and 312.21

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Solution

The fourth proportional to 1,286.10, 1,929.17 and 312.21 is: 468.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.10 : 1,929.17 = 312.21 : x
  2. Step 2: Convert to fraction form
    1,286.10/1,929.17 = 312.21/x
  3. Step 3: Cross multiply
    1,286.10x = 1,929.17 × 312.21
  4. Step 4: Simplify right side
    1,286.10x = 602,306.17
  5. Step 5: Solve for x
    x = 602,306.17/1,286.10
  6. Step 6: Final answer
    x = 468.32

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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.