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Finding the Fourth Proportional to 315.30, 435.20 and 282.50

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Solution

The fourth proportional to 315.30, 435.20 and 282.50 is: 389.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.30 : 435.20 = 282.50 : x
  2. Step 2: Convert to fraction form
    315.30/435.20 = 282.50/x
  3. Step 3: Cross multiply
    315.30x = 435.20 × 282.50
  4. Step 4: Simplify right side
    315.30x = 122,940.41
  5. Step 5: Solve for x
    x = 122,940.41/315.30
  6. Step 6: Final answer
    x = 389.92

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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.