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Finding the Fourth Proportional to 688.20, 949.72 and 393.48

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Solution

The fourth proportional to 688.20, 949.72 and 393.48 is: 543.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.20 : 949.72 = 393.48 : x
  2. Step 2: Convert to fraction form
    688.20/949.72 = 393.48/x
  3. Step 3: Cross multiply
    688.20x = 949.72 × 393.48
  4. Step 4: Simplify right side
    688.20x = 373,695.83
  5. Step 5: Solve for x
    x = 373,695.83/688.20
  6. Step 6: Final answer
    x = 543.00

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.