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Finding the Fourth Proportional to 818.96, 1,228.98 and 386.15

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Solution

The fourth proportional to 818.96, 1,228.98 and 386.15 is: 579.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.96 : 1,228.98 = 386.15 : x
  2. Step 2: Convert to fraction form
    818.96/1,228.98 = 386.15/x
  3. Step 3: Cross multiply
    818.96x = 1,228.98 × 386.15
  4. Step 4: Simplify right side
    818.96x = 474,570.63
  5. Step 5: Solve for x
    x = 474,570.63/818.96
  6. Step 6: Final answer
    x = 579.48

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1.5x scale

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.