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Finding the Fourth Proportional to 1,259.80, 1,888.20 and 869.80

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Solution

The fourth proportional to 1,259.80, 1,888.20 and 869.80 is: 1,303.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,259.80 : 1,888.20 = 869.80 : x
  2. Step 2: Convert to fraction form
    1,259.80/1,888.20 = 869.80/x
  3. Step 3: Cross multiply
    1,259.80x = 1,888.20 × 869.80
  4. Step 4: Simplify right side
    1,259.80x = 1,642,356.36
  5. Step 5: Solve for x
    x = 1,642,356.36/1,259.80
  6. Step 6: Final answer
    x = 1,303.66

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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.