Home / 1,281.02-1,921.39-459.20

Finding the Fourth Proportional to 1,281.02, 1,921.39 and 459.20

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Solution

The fourth proportional to 1,281.02, 1,921.39 and 459.20 is: 688.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.02 : 1,921.39 = 459.20 : x
  2. Step 2: Convert to fraction form
    1,281.02/1,921.39 = 459.20/x
  3. Step 3: Cross multiply
    1,281.02x = 1,921.39 × 459.20
  4. Step 4: Simplify right side
    1,281.02x = 882,305.94
  5. Step 5: Solve for x
    x = 882,305.94/1,281.02
  6. Step 6: Final answer
    x = 688.76

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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.