Home / 1,286.21-1,929.32-312.31

Finding the Fourth Proportional to 1,286.21, 1,929.32 and 312.31

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Solution

The fourth proportional to 1,286.21, 1,929.32 and 312.31 is: 468.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.21 : 1,929.32 = 312.31 : x
  2. Step 2: Convert to fraction form
    1,286.21/1,929.32 = 312.31/x
  3. Step 3: Cross multiply
    1,286.21x = 1,929.32 × 312.31
  4. Step 4: Simplify right side
    1,286.21x = 602,545.93
  5. Step 5: Solve for x
    x = 602,545.93/1,286.21
  6. Step 6: Final answer
    x = 468.47

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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.