Home / 1,285.12-1,927.60-419.40

Finding the Fourth Proportional to 1,285.12, 1,927.60 and 419.40

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Solution

The fourth proportional to 1,285.12, 1,927.60 and 419.40 is: 629.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.12 : 1,927.60 = 419.40 : x
  2. Step 2: Convert to fraction form
    1,285.12/1,927.60 = 419.40/x
  3. Step 3: Cross multiply
    1,285.12x = 1,927.60 × 419.40
  4. Step 4: Simplify right side
    1,285.12x = 808,435.44
  5. Step 5: Solve for x
    x = 808,435.44/1,285.12
  6. Step 6: Final answer
    x = 629.07

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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.