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Finding the Fourth Proportional to 127.50, 191.25 and 42

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Solution

The fourth proportional to 127.50, 191.25 and 42 is: 63

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.50 : 191.25 = 42 : x
  2. Step 2: Convert to fraction form
    127.50/191.25 = 42/x
  3. Step 3: Cross multiply
    127.50x = 191.25 × 42
  4. Step 4: Simplify right side
    127.50x = 8,032.50
  5. Step 5: Solve for x
    x = 8,032.50/127.50
  6. Step 6: Final answer
    x = 63

Related Problems

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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.