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Finding the Fourth Proportional to 838.47, 1,256.35 and 512.85

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Solution

The fourth proportional to 838.47, 1,256.35 and 512.85 is: 768.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    838.47 : 1,256.35 = 512.85 : x
  2. Step 2: Convert to fraction form
    838.47/1,256.35 = 512.85/x
  3. Step 3: Cross multiply
    838.47x = 1,256.35 × 512.85
  4. Step 4: Simplify right side
    838.47x = 644,319.10
  5. Step 5: Solve for x
    x = 644,319.10/838.47
  6. Step 6: Final answer
    x = 768.45

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1.5x scale

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.