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Finding the Fourth Proportional to 900.09, 1,238.89 and 637.65

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Solution

The fourth proportional to 900.09, 1,238.89 and 637.65 is: 877.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    900.09 : 1,238.89 = 637.65 : x
  2. Step 2: Convert to fraction form
    900.09/1,238.89 = 637.65/x
  3. Step 3: Cross multiply
    900.09x = 1,238.89 × 637.65
  4. Step 4: Simplify right side
    900.09x = 789,978.21
  5. Step 5: Solve for x
    x = 789,978.21/900.09
  6. Step 6: Final answer
    x = 877.67

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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.