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Finding the Fourth Proportional to 207.02, 310.53 and 85.20

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Solution

The fourth proportional to 207.02, 310.53 and 85.20 is: 127.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.02 : 310.53 = 85.20 : x
  2. Step 2: Convert to fraction form
    207.02/310.53 = 85.20/x
  3. Step 3: Cross multiply
    207.02x = 310.53 × 85.20
  4. Step 4: Simplify right side
    207.02x = 26,457.16
  5. Step 5: Solve for x
    x = 26,457.16/207.02
  6. Step 6: Final answer
    x = 127.80

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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.