Home / 1,286.55-1,929.80-312.64

Finding the Fourth Proportional to 1,286.55, 1,929.80 and 312.64

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Solution

The fourth proportional to 1,286.55, 1,929.80 and 312.64 is: 468.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.55 : 1,929.80 = 312.64 : x
  2. Step 2: Convert to fraction form
    1,286.55/1,929.80 = 312.64/x
  3. Step 3: Cross multiply
    1,286.55x = 1,929.80 × 312.64
  4. Step 4: Simplify right side
    1,286.55x = 603,332.67
  5. Step 5: Solve for x
    x = 603,332.67/1,286.55
  6. Step 6: Final answer
    x = 468.95

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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.