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Finding the Fourth Proportional to 890.34, 1,336.36 and 428.43

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Solution

The fourth proportional to 890.34, 1,336.36 and 428.43 is: 643.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.34 : 1,336.36 = 428.43 : x
  2. Step 2: Convert to fraction form
    890.34/1,336.36 = 428.43/x
  3. Step 3: Cross multiply
    890.34x = 1,336.36 × 428.43
  4. Step 4: Simplify right side
    890.34x = 572,536.71
  5. Step 5: Solve for x
    x = 572,536.71/890.34
  6. Step 6: Final answer
    x = 643.06

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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.