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Finding the Fourth Proportional to 690.20, 950.70 and 565.40

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Solution

The fourth proportional to 690.20, 950.70 and 565.40 is: 778.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.20 : 950.70 = 565.40 : x
  2. Step 2: Convert to fraction form
    690.20/950.70 = 565.40/x
  3. Step 3: Cross multiply
    690.20x = 950.70 × 565.40
  4. Step 4: Simplify right side
    690.20x = 537,525.78
  5. Step 5: Solve for x
    x = 537,525.78/690.20
  6. Step 6: Final answer
    x = 778.80

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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.