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Finding the Fourth Proportional to 860.10, 1,290.57 and 421.62

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Solution

The fourth proportional to 860.10, 1,290.57 and 421.62 is: 632.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.10 : 1,290.57 = 421.62 : x
  2. Step 2: Convert to fraction form
    860.10/1,290.57 = 421.62/x
  3. Step 3: Cross multiply
    860.10x = 1,290.57 × 421.62
  4. Step 4: Simplify right side
    860.10x = 544,130.12
  5. Step 5: Solve for x
    x = 544,130.12/860.10
  6. Step 6: Final answer
    x = 632.64

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Double scale
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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.