Home / 1,220.12-1,830.40-429.56

Finding the Fourth Proportional to 1,220.12, 1,830.40 and 429.56

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Solution

The fourth proportional to 1,220.12, 1,830.40 and 429.56 is: 644.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.12 : 1,830.40 = 429.56 : x
  2. Step 2: Convert to fraction form
    1,220.12/1,830.40 = 429.56/x
  3. Step 3: Cross multiply
    1,220.12x = 1,830.40 × 429.56
  4. Step 4: Simplify right side
    1,220.12x = 786,257.47
  5. Step 5: Solve for x
    x = 786,257.47/1,220.12
  6. Step 6: Final answer
    x = 644.41

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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.