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Finding the Fourth Proportional to 900.90, 1,242.54 and 690.75

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Solution

The fourth proportional to 900.90, 1,242.54 and 690.75 is: 952.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    900.90 : 1,242.54 = 690.75 : x
  2. Step 2: Convert to fraction form
    900.90/1,242.54 = 690.75/x
  3. Step 3: Cross multiply
    900.90x = 1,242.54 × 690.75
  4. Step 4: Simplify right side
    900.90x = 858,284.51
  5. Step 5: Solve for x
    x = 858,284.51/900.90
  6. Step 6: Final answer
    x = 952.70

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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.