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Finding the Fourth Proportional to 421.79, 633.29 and 260.19

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Solution

The fourth proportional to 421.79, 633.29 and 260.19 is: 390.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.79 : 633.29 = 260.19 : x
  2. Step 2: Convert to fraction form
    421.79/633.29 = 260.19/x
  3. Step 3: Cross multiply
    421.79x = 633.29 × 260.19
  4. Step 4: Simplify right side
    421.79x = 164,774.42
  5. Step 5: Solve for x
    x = 164,774.42/421.79
  6. Step 6: Final answer
    x = 390.66

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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.