Home / 1,285.19-1,928.09-419.50

Finding the Fourth Proportional to 1,285.19, 1,928.09 and 419.50

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Solution

The fourth proportional to 1,285.19, 1,928.09 and 419.50 is: 629.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.19 : 1,928.09 = 419.50 : x
  2. Step 2: Convert to fraction form
    1,285.19/1,928.09 = 419.50/x
  3. Step 3: Cross multiply
    1,285.19x = 1,928.09 × 419.50
  4. Step 4: Simplify right side
    1,285.19x = 808,833.76
  5. Step 5: Solve for x
    x = 808,833.76/1,285.19
  6. Step 6: Final answer
    x = 629.35

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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.