Home / 1,281.20-1,921.75-415.51

Finding the Fourth Proportional to 1,281.20, 1,921.75 and 415.51

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Solution

The fourth proportional to 1,281.20, 1,921.75 and 415.51 is: 623.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.20 : 1,921.75 = 415.51 : x
  2. Step 2: Convert to fraction form
    1,281.20/1,921.75 = 415.51/x
  3. Step 3: Cross multiply
    1,281.20x = 1,921.75 × 415.51
  4. Step 4: Simplify right side
    1,281.20x = 798,500.50
  5. Step 5: Solve for x
    x = 798,500.50/1,281.20
  6. Step 6: Final answer
    x = 623.25

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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.