Home / 1,403.40-2,105.64-429.78

Finding the Fourth Proportional to 1,403.40, 2,105.64 and 429.78

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Solution

The fourth proportional to 1,403.40, 2,105.64 and 429.78 is: 644.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,403.40 : 2,105.64 = 429.78 : x
  2. Step 2: Convert to fraction form
    1,403.40/2,105.64 = 429.78/x
  3. Step 3: Cross multiply
    1,403.40x = 2,105.64 × 429.78
  4. Step 4: Simplify right side
    1,403.40x = 904,961.96
  5. Step 5: Solve for x
    x = 904,961.96/1,403.40
  6. Step 6: Final answer
    x = 644.84

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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.