Home / 1,438.10-1,985.81-1,391.66

Finding the Fourth Proportional to 1,438.10, 1,985.81 and 1,391.66

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Solution

The fourth proportional to 1,438.10, 1,985.81 and 1,391.66 is: 1,921.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,438.10 : 1,985.81 = 1,391.66 : x
  2. Step 2: Convert to fraction form
    1,438.10/1,985.81 = 1,391.66/x
  3. Step 3: Cross multiply
    1,438.10x = 1,985.81 × 1,391.66
  4. Step 4: Simplify right side
    1,438.10x = 2,763,572.34
  5. Step 5: Solve for x
    x = 2,763,572.34/1,438.10
  6. Step 6: Final answer
    x = 1,921.68

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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.