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Finding the Fourth Proportional to 99.90, 145.80 and 99.90

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Solution

The fourth proportional to 99.90, 145.80 and 99.90 is: 145.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    99.90 : 145.80 = 99.90 : x
  2. Step 2: Convert to fraction form
    99.90/145.80 = 99.90/x
  3. Step 3: Cross multiply
    99.90x = 145.80 × 99.90
  4. Step 4: Simplify right side
    99.90x = 14,565.42
  5. Step 5: Solve for x
    x = 14,565.42/99.90
  6. Step 6: Final answer
    x = 145.80

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Why These Related Problems?

These problems maintain the same ratio (1.46) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.