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Finding the Fourth Proportional to 860.36, 1,290.56 and 211.09

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Solution

The fourth proportional to 860.36, 1,290.56 and 211.09 is: 316.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.36 : 1,290.56 = 211.09 : x
  2. Step 2: Convert to fraction form
    860.36/1,290.56 = 211.09/x
  3. Step 3: Cross multiply
    860.36x = 1,290.56 × 211.09
  4. Step 4: Simplify right side
    860.36x = 272,424.31
  5. Step 5: Solve for x
    x = 272,424.31/860.36
  6. Step 6: Final answer
    x = 316.64

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1.5x scale

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.