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Finding the Fourth Proportional to 1,380.80, 1,904.19 and 909.02

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Solution

The fourth proportional to 1,380.80, 1,904.19 and 909.02 is: 1,253.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.80 : 1,904.19 = 909.02 : x
  2. Step 2: Convert to fraction form
    1,380.80/1,904.19 = 909.02/x
  3. Step 3: Cross multiply
    1,380.80x = 1,904.19 × 909.02
  4. Step 4: Simplify right side
    1,380.80x = 1,730,946.79
  5. Step 5: Solve for x
    x = 1,730,946.79/1,380.80
  6. Step 6: Final answer
    x = 1,253.58

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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.