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Finding the Fourth Proportional to 340.90, 511.35 and 286.90

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Solution

The fourth proportional to 340.90, 511.35 and 286.90 is: 430.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    340.90 : 511.35 = 286.90 : x
  2. Step 2: Convert to fraction form
    340.90/511.35 = 286.90/x
  3. Step 3: Cross multiply
    340.90x = 511.35 × 286.90
  4. Step 4: Simplify right side
    340.90x = 146,706.32
  5. Step 5: Solve for x
    x = 146,706.32/340.90
  6. Step 6: Final answer
    x = 430.35

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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.