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Finding the Fourth Proportional to 30.51, 42 and 30.42

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Solution

The fourth proportional to 30.51, 42 and 30.42 is: 41.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.51 : 42 = 30.42 : x
  2. Step 2: Convert to fraction form
    30.51/42 = 30.42/x
  3. Step 3: Cross multiply
    30.51x = 42 × 30.42
  4. Step 4: Simplify right side
    30.51x = 1,277.64
  5. Step 5: Solve for x
    x = 1,277.64/30.51
  6. Step 6: Final answer
    x = 41.88

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1.5x scale

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.