Home / 1,281.18-1,921.78-415.49

Finding the Fourth Proportional to 1,281.18, 1,921.78 and 415.49

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Solution

The fourth proportional to 1,281.18, 1,921.78 and 415.49 is: 623.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.18 : 1,921.78 = 415.49 : x
  2. Step 2: Convert to fraction form
    1,281.18/1,921.78 = 415.49/x
  3. Step 3: Cross multiply
    1,281.18x = 1,921.78 × 415.49
  4. Step 4: Simplify right side
    1,281.18x = 798,480.37
  5. Step 5: Solve for x
    x = 798,480.37/1,281.18
  6. Step 6: Final answer
    x = 623.24

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.