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Finding the Fourth Proportional to 1,239, 1,859.76 and 509

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Solution

The fourth proportional to 1,239, 1,859.76 and 509 is: 764.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,239 : 1,859.76 = 509 : x
  2. Step 2: Convert to fraction form
    1,239/1,859.76 = 509/x
  3. Step 3: Cross multiply
    1,239x = 1,859.76 × 509
  4. Step 4: Simplify right side
    1,239x = 946,617.84
  5. Step 5: Solve for x
    x = 946,617.84/1,239
  6. Step 6: Final answer
    x = 764.02

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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.