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Finding the Fourth Proportional to 838.58, 1,256.45 and 509.31

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Solution

The fourth proportional to 838.58, 1,256.45 and 509.31 is: 763.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.58 : 1,256.45 = 509.31 : x
  2. Step 2: Convert to fraction form
    838.58/1,256.45 = 509.31/x
  3. Step 3: Cross multiply
    838.58x = 1,256.45 × 509.31
  4. Step 4: Simplify right side
    838.58x = 639,920.00
  5. Step 5: Solve for x
    x = 639,920.00/838.58
  6. Step 6: Final answer
    x = 763.10

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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.