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Finding the Fourth Proportional to 1,321.30, 1,820.64 and 900.91

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Solution

The fourth proportional to 1,321.30, 1,820.64 and 900.91 is: 1,241.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.30 : 1,820.64 = 900.91 : x
  2. Step 2: Convert to fraction form
    1,321.30/1,820.64 = 900.91/x
  3. Step 3: Cross multiply
    1,321.30x = 1,820.64 × 900.91
  4. Step 4: Simplify right side
    1,321.30x = 1,640,232.78
  5. Step 5: Solve for x
    x = 1,640,232.78/1,321.30
  6. Step 6: Final answer
    x = 1,241.38

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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.