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Finding the Fourth Proportional to 211.31, 290.99 and 145.70

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Solution

The fourth proportional to 211.31, 290.99 and 145.70 is: 200.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    211.31 : 290.99 = 145.70 : x
  2. Step 2: Convert to fraction form
    211.31/290.99 = 145.70/x
  3. Step 3: Cross multiply
    211.31x = 290.99 × 145.70
  4. Step 4: Simplify right side
    211.31x = 42,397.24
  5. Step 5: Solve for x
    x = 42,397.24/211.31
  6. Step 6: Final answer
    x = 200.64

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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.