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Finding the Fourth Proportional to 879.20, 1,213.26 and 486.20

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Solution

The fourth proportional to 879.20, 1,213.26 and 486.20 is: 670.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.20 : 1,213.26 = 486.20 : x
  2. Step 2: Convert to fraction form
    879.20/1,213.26 = 486.20/x
  3. Step 3: Cross multiply
    879.20x = 1,213.26 × 486.20
  4. Step 4: Simplify right side
    879.20x = 589,880.95
  5. Step 5: Solve for x
    x = 589,880.95/879.20
  6. Step 6: Final answer
    x = 670.93

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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.