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Finding the Fourth Proportional to 778.68, 1,075.06 and 637.20

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Solution

The fourth proportional to 778.68, 1,075.06 and 637.20 is: 879.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.68 : 1,075.06 = 637.20 : x
  2. Step 2: Convert to fraction form
    778.68/1,075.06 = 637.20/x
  3. Step 3: Cross multiply
    778.68x = 1,075.06 × 637.20
  4. Step 4: Simplify right side
    778.68x = 685,028.23
  5. Step 5: Solve for x
    x = 685,028.23/778.68
  6. Step 6: Final answer
    x = 879.73

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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.