Home / 1,285.41-1,928.15-407.91

Finding the Fourth Proportional to 1,285.41, 1,928.15 and 407.91

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Solution

The fourth proportional to 1,285.41, 1,928.15 and 407.91 is: 611.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.41 : 1,928.15 = 407.91 : x
  2. Step 2: Convert to fraction form
    1,285.41/1,928.15 = 407.91/x
  3. Step 3: Cross multiply
    1,285.41x = 1,928.15 × 407.91
  4. Step 4: Simplify right side
    1,285.41x = 786,518.39
  5. Step 5: Solve for x
    x = 786,518.39/1,285.41
  6. Step 6: Final answer
    x = 611.88

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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.