Home / 1,285.20-1,927.50-407.76

Finding the Fourth Proportional to 1,285.20, 1,927.50 and 407.76

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Solution

The fourth proportional to 1,285.20, 1,927.50 and 407.76 is: 611.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,285.20 : 1,927.50 = 407.76 : x
  2. Step 2: Convert to fraction form
    1,285.20/1,927.50 = 407.76/x
  3. Step 3: Cross multiply
    1,285.20x = 1,927.50 × 407.76
  4. Step 4: Simplify right side
    1,285.20x = 785,957.40
  5. Step 5: Solve for x
    x = 785,957.40/1,285.20
  6. Step 6: Final answer
    x = 611.54

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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.