Home / 1,285.28-1,928.22-419.60

Finding the Fourth Proportional to 1,285.28, 1,928.22 and 419.60

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Solution

The fourth proportional to 1,285.28, 1,928.22 and 419.60 is: 629.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.28 : 1,928.22 = 419.60 : x
  2. Step 2: Convert to fraction form
    1,285.28/1,928.22 = 419.60/x
  3. Step 3: Cross multiply
    1,285.28x = 1,928.22 × 419.60
  4. Step 4: Simplify right side
    1,285.28x = 809,081.11
  5. Step 5: Solve for x
    x = 809,081.11/1,285.28
  6. Step 6: Final answer
    x = 629.50

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1.5x scale

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.