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Finding the Fourth Proportional to 900.20, 1,242.08 and 507.15

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Solution

The fourth proportional to 900.20, 1,242.08 and 507.15 is: 699.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    900.20 : 1,242.08 = 507.15 : x
  2. Step 2: Convert to fraction form
    900.20/1,242.08 = 507.15/x
  3. Step 3: Cross multiply
    900.20x = 1,242.08 × 507.15
  4. Step 4: Simplify right side
    900.20x = 629,918.34
  5. Step 5: Solve for x
    x = 629,918.34/900.20
  6. Step 6: Final answer
    x = 699.76

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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.