Home / 850.05-1,275.10-405.20

Finding the Fourth Proportional to 850.05, 1,275.10 and 405.20

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Solution

The fourth proportional to 850.05, 1,275.10 and 405.20 is: 607.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    850.05 : 1,275.10 = 405.20 : x
  2. Step 2: Convert to fraction form
    850.05/1,275.10 = 405.20/x
  3. Step 3: Cross multiply
    850.05x = 1,275.10 × 405.20
  4. Step 4: Simplify right side
    850.05x = 516,670.52
  5. Step 5: Solve for x
    x = 516,670.52/850.05
  6. Step 6: Final answer
    x = 607.81

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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.