Home / 1,281.32-1,921.86-415.64

Finding the Fourth Proportional to 1,281.32, 1,921.86 and 415.64

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Solution

The fourth proportional to 1,281.32, 1,921.86 and 415.64 is: 623.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.32 : 1,921.86 = 415.64 : x
  2. Step 2: Convert to fraction form
    1,281.32/1,921.86 = 415.64/x
  3. Step 3: Cross multiply
    1,281.32x = 1,921.86 × 415.64
  4. Step 4: Simplify right side
    1,281.32x = 798,801.89
  5. Step 5: Solve for x
    x = 798,801.89/1,281.32
  6. Step 6: Final answer
    x = 623.42

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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.