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Finding the Fourth Proportional to 398.36, 549.98 and 315.80

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Solution

The fourth proportional to 398.36, 549.98 and 315.80 is: 436.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.36 : 549.98 = 315.80 : x
  2. Step 2: Convert to fraction form
    398.36/549.98 = 315.80/x
  3. Step 3: Cross multiply
    398.36x = 549.98 × 315.80
  4. Step 4: Simplify right side
    398.36x = 173,683.68
  5. Step 5: Solve for x
    x = 173,683.68/398.36
  6. Step 6: Final answer
    x = 436.00

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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.