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Finding the Fourth Proportional to 261.79, 361.32 and 218.05

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Solution

The fourth proportional to 261.79, 361.32 and 218.05 is: 300.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    261.79 : 361.32 = 218.05 : x
  2. Step 2: Convert to fraction form
    261.79/361.32 = 218.05/x
  3. Step 3: Cross multiply
    261.79x = 361.32 × 218.05
  4. Step 4: Simplify right side
    261.79x = 78,785.83
  5. Step 5: Solve for x
    x = 78,785.83/261.79
  6. Step 6: Final answer
    x = 300.95

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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.