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Finding the Fourth Proportional to 680.42, 1,020.18 and 290

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Solution

The fourth proportional to 680.42, 1,020.18 and 290 is: 434.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.42 : 1,020.18 = 290 : x
  2. Step 2: Convert to fraction form
    680.42/1,020.18 = 290/x
  3. Step 3: Cross multiply
    680.42x = 1,020.18 × 290
  4. Step 4: Simplify right side
    680.42x = 295,852.20
  5. Step 5: Solve for x
    x = 295,852.20/680.42
  6. Step 6: Final answer
    x = 434.81

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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.