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Finding the Fourth Proportional to 30.02, 45.18 and 21.05

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Solution

The fourth proportional to 30.02, 45.18 and 21.05 is: 31.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.02 : 45.18 = 21.05 : x
  2. Step 2: Convert to fraction form
    30.02/45.18 = 21.05/x
  3. Step 3: Cross multiply
    30.02x = 45.18 × 21.05
  4. Step 4: Simplify right side
    30.02x = 950.81
  5. Step 5: Solve for x
    x = 950.81/30.02
  6. Step 6: Final answer
    x = 31.68

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.