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Finding the Fourth Proportional to 290.80, 435.64 and 260

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Solution

The fourth proportional to 290.80, 435.64 and 260 is: 389.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.80 : 435.64 = 260 : x
  2. Step 2: Convert to fraction form
    290.80/435.64 = 260/x
  3. Step 3: Cross multiply
    290.80x = 435.64 × 260
  4. Step 4: Simplify right side
    290.80x = 113,266.40
  5. Step 5: Solve for x
    x = 113,266.40/290.80
  6. Step 6: Final answer
    x = 389.50

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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.