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Finding the Fourth Proportional to 151.80, 209.51 and 99.30

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Solution

The fourth proportional to 151.80, 209.51 and 99.30 is: 137.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    151.80 : 209.51 = 99.30 : x
  2. Step 2: Convert to fraction form
    151.80/209.51 = 99.30/x
  3. Step 3: Cross multiply
    151.80x = 209.51 × 99.30
  4. Step 4: Simplify right side
    151.80x = 20,804.34
  5. Step 5: Solve for x
    x = 20,804.34/151.80
  6. Step 6: Final answer
    x = 137.05

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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.