Home / 1,378.08-1,901.30-788.40

Finding the Fourth Proportional to 1,378.08, 1,901.30 and 788.40

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Solution

The fourth proportional to 1,378.08, 1,901.30 and 788.40 is: 1,087.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.08 : 1,901.30 = 788.40 : x
  2. Step 2: Convert to fraction form
    1,378.08/1,901.30 = 788.40/x
  3. Step 3: Cross multiply
    1,378.08x = 1,901.30 × 788.40
  4. Step 4: Simplify right side
    1,378.08x = 1,498,984.92
  5. Step 5: Solve for x
    x = 1,498,984.92/1,378.08
  6. Step 6: Final answer
    x = 1,087.73

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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.