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Finding the Fourth Proportional to 210.86, 290.88 and 145.40

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Solution

The fourth proportional to 210.86, 290.88 and 145.40 is: 200.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.86 : 290.88 = 145.40 : x
  2. Step 2: Convert to fraction form
    210.86/290.88 = 145.40/x
  3. Step 3: Cross multiply
    210.86x = 290.88 × 145.40
  4. Step 4: Simplify right side
    210.86x = 42,293.95
  5. Step 5: Solve for x
    x = 42,293.95/210.86
  6. Step 6: Final answer
    x = 200.58

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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.