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Finding the Fourth Proportional to 839.84, 1,159.12 and 490.72

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Solution

The fourth proportional to 839.84, 1,159.12 and 490.72 is: 677.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.84 : 1,159.12 = 490.72 : x
  2. Step 2: Convert to fraction form
    839.84/1,159.12 = 490.72/x
  3. Step 3: Cross multiply
    839.84x = 1,159.12 × 490.72
  4. Step 4: Simplify right side
    839.84x = 568,803.37
  5. Step 5: Solve for x
    x = 568,803.37/839.84
  6. Step 6: Final answer
    x = 677.28

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.