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Finding the Fourth Proportional to 998.79, 1,378.30 and 579.13

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Solution

The fourth proportional to 998.79, 1,378.30 and 579.13 is: 799.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    998.79 : 1,378.30 = 579.13 : x
  2. Step 2: Convert to fraction form
    998.79/1,378.30 = 579.13/x
  3. Step 3: Cross multiply
    998.79x = 1,378.30 × 579.13
  4. Step 4: Simplify right side
    998.79x = 798,214.88
  5. Step 5: Solve for x
    x = 798,214.88/998.79
  6. Step 6: Final answer
    x = 799.18

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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.