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Finding the Fourth Proportional to 284.99, 390.72 and 279.80

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Solution

The fourth proportional to 284.99, 390.72 and 279.80 is: 383.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.99 : 390.72 = 279.80 : x
  2. Step 2: Convert to fraction form
    284.99/390.72 = 279.80/x
  3. Step 3: Cross multiply
    284.99x = 390.72 × 279.80
  4. Step 4: Simplify right side
    284.99x = 109,322.97
  5. Step 5: Solve for x
    x = 109,322.97/284.99
  6. Step 6: Final answer
    x = 383.60

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.