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Finding the Fourth Proportional to 290.80, 436.28 and 98.40

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Solution

The fourth proportional to 290.80, 436.28 and 98.40 is: 147.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.80 : 436.28 = 98.40 : x
  2. Step 2: Convert to fraction form
    290.80/436.28 = 98.40/x
  3. Step 3: Cross multiply
    290.80x = 436.28 × 98.40
  4. Step 4: Simplify right side
    290.80x = 42,929.95
  5. Step 5: Solve for x
    x = 42,929.95/290.80
  6. Step 6: Final answer
    x = 147.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.