Home / 1,511.20-2,084.78-921.70

Finding the Fourth Proportional to 1,511.20, 2,084.78 and 921.70

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Solution

The fourth proportional to 1,511.20, 2,084.78 and 921.70 is: 1,271.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,511.20 : 2,084.78 = 921.70 : x
  2. Step 2: Convert to fraction form
    1,511.20/2,084.78 = 921.70/x
  3. Step 3: Cross multiply
    1,511.20x = 2,084.78 × 921.70
  4. Step 4: Simplify right side
    1,511.20x = 1,921,541.73
  5. Step 5: Solve for x
    x = 1,921,541.73/1,511.20
  6. Step 6: Final answer
    x = 1,271.53

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.