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Finding the Fourth Proportional to 698.80, 964.40 and 419.05

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Solution

The fourth proportional to 698.80, 964.40 and 419.05 is: 578.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    698.80 : 964.40 = 419.05 : x
  2. Step 2: Convert to fraction form
    698.80/964.40 = 419.05/x
  3. Step 3: Cross multiply
    698.80x = 964.40 × 419.05
  4. Step 4: Simplify right side
    698.80x = 404,125.95
  5. Step 5: Solve for x
    x = 404,125.95/698.80
  6. Step 6: Final answer
    x = 578.31

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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.