Home / 1,281.36-1,921.68-415.80

Finding the Fourth Proportional to 1,281.36, 1,921.68 and 415.80

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Solution

The fourth proportional to 1,281.36, 1,921.68 and 415.80 is: 623.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.36 : 1,921.68 = 415.80 : x
  2. Step 2: Convert to fraction form
    1,281.36/1,921.68 = 415.80/x
  3. Step 3: Cross multiply
    1,281.36x = 1,921.68 × 415.80
  4. Step 4: Simplify right side
    1,281.36x = 799,034.54
  5. Step 5: Solve for x
    x = 799,034.54/1,281.36
  6. Step 6: Final answer
    x = 623.58

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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.