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Finding the Fourth Proportional to 289.89, 399.72 and 260.40

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Solution

The fourth proportional to 289.89, 399.72 and 260.40 is: 359.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.89 : 399.72 = 260.40 : x
  2. Step 2: Convert to fraction form
    289.89/399.72 = 260.40/x
  3. Step 3: Cross multiply
    289.89x = 399.72 × 260.40
  4. Step 4: Simplify right side
    289.89x = 104,087.09
  5. Step 5: Solve for x
    x = 104,087.09/289.89
  6. Step 6: Final answer
    x = 359.06

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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.