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Finding the Fourth Proportional to 521.57, 719.79 and 288.68

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Solution

The fourth proportional to 521.57, 719.79 and 288.68 is: 398.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.57 : 719.79 = 288.68 : x
  2. Step 2: Convert to fraction form
    521.57/719.79 = 288.68/x
  3. Step 3: Cross multiply
    521.57x = 719.79 × 288.68
  4. Step 4: Simplify right side
    521.57x = 207,788.98
  5. Step 5: Solve for x
    x = 207,788.98/521.57
  6. Step 6: Final answer
    x = 398.39

Related Problems

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Similar ratio
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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.