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Finding the Fourth Proportional to 710.80, 980.90 and 400.28

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Solution

The fourth proportional to 710.80, 980.90 and 400.28 is: 552.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    710.80 : 980.90 = 400.28 : x
  2. Step 2: Convert to fraction form
    710.80/980.90 = 400.28/x
  3. Step 3: Cross multiply
    710.80x = 980.90 × 400.28
  4. Step 4: Simplify right side
    710.80x = 392,634.65
  5. Step 5: Solve for x
    x = 392,634.65/710.80
  6. Step 6: Final answer
    x = 552.38

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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.