Home / 1,390.20-1,918.93-800.88

Finding the Fourth Proportional to 1,390.20, 1,918.93 and 800.88

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Solution

The fourth proportional to 1,390.20, 1,918.93 and 800.88 is: 1,105.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.20 : 1,918.93 = 800.88 : x
  2. Step 2: Convert to fraction form
    1,390.20/1,918.93 = 800.88/x
  3. Step 3: Cross multiply
    1,390.20x = 1,918.93 × 800.88
  4. Step 4: Simplify right side
    1,390.20x = 1,536,832.66
  5. Step 5: Solve for x
    x = 1,536,832.66/1,390.20
  6. Step 6: Final answer
    x = 1,105.48

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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.