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Finding the Fourth Proportional to 860.95, 1,290.48 and 340.80

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Solution

The fourth proportional to 860.95, 1,290.48 and 340.80 is: 510.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.95 : 1,290.48 = 340.80 : x
  2. Step 2: Convert to fraction form
    860.95/1,290.48 = 340.80/x
  3. Step 3: Cross multiply
    860.95x = 1,290.48 × 340.80
  4. Step 4: Simplify right side
    860.95x = 439,795.58
  5. Step 5: Solve for x
    x = 439,795.58/860.95
  6. Step 6: Final answer
    x = 510.83

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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.