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Finding the Fourth Proportional to 860.09, 1,290.11 and 304.79

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Solution

The fourth proportional to 860.09, 1,290.11 and 304.79 is: 457.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.09 : 1,290.11 = 304.79 : x
  2. Step 2: Convert to fraction form
    860.09/1,290.11 = 304.79/x
  3. Step 3: Cross multiply
    860.09x = 1,290.11 × 304.79
  4. Step 4: Simplify right side
    860.09x = 393,204.65
  5. Step 5: Solve for x
    x = 393,204.65/860.09
  6. Step 6: Final answer
    x = 457.17

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Half scale
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Double scale
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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.