Home / 1,390.34-1,919.15-801.11

Finding the Fourth Proportional to 1,390.34, 1,919.15 and 801.11

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Solution

The fourth proportional to 1,390.34, 1,919.15 and 801.11 is: 1,105.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,390.34 : 1,919.15 = 801.11 : x
  2. Step 2: Convert to fraction form
    1,390.34/1,919.15 = 801.11/x
  3. Step 3: Cross multiply
    1,390.34x = 1,919.15 × 801.11
  4. Step 4: Simplify right side
    1,390.34x = 1,537,436.66
  5. Step 5: Solve for x
    x = 1,537,436.66/1,390.34
  6. Step 6: Final answer
    x = 1,105.80

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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.