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Finding the Fourth Proportional to 780.16, 1,170.12 and 260.18

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Solution

The fourth proportional to 780.16, 1,170.12 and 260.18 is: 390.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.16 : 1,170.12 = 260.18 : x
  2. Step 2: Convert to fraction form
    780.16/1,170.12 = 260.18/x
  3. Step 3: Cross multiply
    780.16x = 1,170.12 × 260.18
  4. Step 4: Simplify right side
    780.16x = 304,441.82
  5. Step 5: Solve for x
    x = 304,441.82/780.16
  6. Step 6: Final answer
    x = 390.23

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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.