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Finding the Fourth Proportional to 1,720.33, 2,580.49 and 421.78

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Solution

The fourth proportional to 1,720.33, 2,580.49 and 421.78 is: 632.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,720.33 : 2,580.49 = 421.78 : x
  2. Step 2: Convert to fraction form
    1,720.33/2,580.49 = 421.78/x
  3. Step 3: Cross multiply
    1,720.33x = 2,580.49 × 421.78
  4. Step 4: Simplify right side
    1,720.33x = 1,088,404.47
  5. Step 5: Solve for x
    x = 1,088,404.47/1,720.33
  6. Step 6: Final answer
    x = 632.67

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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.