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Finding the Fourth Proportional to 650.55, 897.78 and 388.72

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Solution

The fourth proportional to 650.55, 897.78 and 388.72 is: 536.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    650.55 : 897.78 = 388.72 : x
  2. Step 2: Convert to fraction form
    650.55/897.78 = 388.72/x
  3. Step 3: Cross multiply
    650.55x = 897.78 × 388.72
  4. Step 4: Simplify right side
    650.55x = 348,985.04
  5. Step 5: Solve for x
    x = 348,985.04/650.55
  6. Step 6: Final answer
    x = 536.45

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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.