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Finding the Fourth Proportional to 210.09, 289.86 and 127.20

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Solution

The fourth proportional to 210.09, 289.86 and 127.20 is: 175.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.09 : 289.86 = 127.20 : x
  2. Step 2: Convert to fraction form
    210.09/289.86 = 127.20/x
  3. Step 3: Cross multiply
    210.09x = 289.86 × 127.20
  4. Step 4: Simplify right side
    210.09x = 36,870.19
  5. Step 5: Solve for x
    x = 36,870.19/210.09
  6. Step 6: Final answer
    x = 175.50

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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.