Home / 1,285.06-1,927.80-419.20

Finding the Fourth Proportional to 1,285.06, 1,927.80 and 419.20

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Solution

The fourth proportional to 1,285.06, 1,927.80 and 419.20 is: 628.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.06 : 1,927.80 = 419.20 : x
  2. Step 2: Convert to fraction form
    1,285.06/1,927.80 = 419.20/x
  3. Step 3: Cross multiply
    1,285.06x = 1,927.80 × 419.20
  4. Step 4: Simplify right side
    1,285.06x = 808,133.76
  5. Step 5: Solve for x
    x = 808,133.76/1,285.06
  6. Step 6: Final answer
    x = 628.87

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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.