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Finding the Fourth Proportional to 1,681.40, 2,520.72 and 641.21

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Solution

The fourth proportional to 1,681.40, 2,520.72 and 641.21 is: 961.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,681.40 : 2,520.72 = 641.21 : x
  2. Step 2: Convert to fraction form
    1,681.40/2,520.72 = 641.21/x
  3. Step 3: Cross multiply
    1,681.40x = 2,520.72 × 641.21
  4. Step 4: Simplify right side
    1,681.40x = 1,616,298.27
  5. Step 5: Solve for x
    x = 1,616,298.27/1,681.40
  6. Step 6: Final answer
    x = 961.28

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.