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Finding the Fourth Proportional to 521.40, 719.80 and 300.31

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Solution

The fourth proportional to 521.40, 719.80 and 300.31 is: 414.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.40 : 719.80 = 300.31 : x
  2. Step 2: Convert to fraction form
    521.40/719.80 = 300.31/x
  3. Step 3: Cross multiply
    521.40x = 719.80 × 300.31
  4. Step 4: Simplify right side
    521.40x = 216,164.81
  5. Step 5: Solve for x
    x = 216,164.81/521.40
  6. Step 6: Final answer
    x = 414.58

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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.