Home / 1,286.39-1,929.56-312.50

Finding the Fourth Proportional to 1,286.39, 1,929.56 and 312.50

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Solution

The fourth proportional to 1,286.39, 1,929.56 and 312.50 is: 468.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.39 : 1,929.56 = 312.50 : x
  2. Step 2: Convert to fraction form
    1,286.39/1,929.56 = 312.50/x
  3. Step 3: Cross multiply
    1,286.39x = 1,929.56 × 312.50
  4. Step 4: Simplify right side
    1,286.39x = 602,976.29
  5. Step 5: Solve for x
    x = 602,976.29/1,286.39
  6. Step 6: Final answer
    x = 468.74

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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.