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Finding the Fourth Proportional to 889.70, 1,228.20 and 668.72

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Solution

The fourth proportional to 889.70, 1,228.20 and 668.72 is: 923.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    889.70 : 1,228.20 = 668.72 : x
  2. Step 2: Convert to fraction form
    889.70/1,228.20 = 668.72/x
  3. Step 3: Cross multiply
    889.70x = 1,228.20 × 668.72
  4. Step 4: Simplify right side
    889.70x = 821,322.47
  5. Step 5: Solve for x
    x = 821,322.47/889.70
  6. Step 6: Final answer
    x = 923.14

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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.