Home / 1,285.47-1,928.14-419.72

Finding the Fourth Proportional to 1,285.47, 1,928.14 and 419.72

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Solution

The fourth proportional to 1,285.47, 1,928.14 and 419.72 is: 629.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.47 : 1,928.14 = 419.72 : x
  2. Step 2: Convert to fraction form
    1,285.47/1,928.14 = 419.72/x
  3. Step 3: Cross multiply
    1,285.47x = 1,928.14 × 419.72
  4. Step 4: Simplify right side
    1,285.47x = 809,268.23
  5. Step 5: Solve for x
    x = 809,268.23/1,285.47
  6. Step 6: Final answer
    x = 629.55

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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.