Home / 1,420.20-2,127.78-771.30

Finding the Fourth Proportional to 1,420.20, 2,127.78 and 771.30

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Solution

The fourth proportional to 1,420.20, 2,127.78 and 771.30 is: 1,155.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.20 : 2,127.78 = 771.30 : x
  2. Step 2: Convert to fraction form
    1,420.20/2,127.78 = 771.30/x
  3. Step 3: Cross multiply
    1,420.20x = 2,127.78 × 771.30
  4. Step 4: Simplify right side
    1,420.20x = 1,641,156.71
  5. Step 5: Solve for x
    x = 1,641,156.71/1,420.20
  6. Step 6: Final answer
    x = 1,155.58

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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.