Home / 1,390.12-1,917.78-1,179.40

Finding the Fourth Proportional to 1,390.12, 1,917.78 and 1,179.40

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Solution

The fourth proportional to 1,390.12, 1,917.78 and 1,179.40 is: 1,627.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.12 : 1,917.78 = 1,179.40 : x
  2. Step 2: Convert to fraction form
    1,390.12/1,917.78 = 1,179.40/x
  3. Step 3: Cross multiply
    1,390.12x = 1,917.78 × 1,179.40
  4. Step 4: Simplify right side
    1,390.12x = 2,261,829.73
  5. Step 5: Solve for x
    x = 2,261,829.73/1,390.12
  6. Step 6: Final answer
    x = 1,627.08

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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.