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Finding the Fourth Proportional to 618.79, 853.95 and 356.80

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Solution

The fourth proportional to 618.79, 853.95 and 356.80 is: 492.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.79 : 853.95 = 356.80 : x
  2. Step 2: Convert to fraction form
    618.79/853.95 = 356.80/x
  3. Step 3: Cross multiply
    618.79x = 853.95 × 356.80
  4. Step 4: Simplify right side
    618.79x = 304,689.36
  5. Step 5: Solve for x
    x = 304,689.36/618.79
  6. Step 6: Final answer
    x = 492.40

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1.5x scale

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.