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Finding the Fourth Proportional to 970.19, 1,338.25 and 638.50

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Solution

The fourth proportional to 970.19, 1,338.25 and 638.50 is: 880.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    970.19 : 1,338.25 = 638.50 : x
  2. Step 2: Convert to fraction form
    970.19/1,338.25 = 638.50/x
  3. Step 3: Cross multiply
    970.19x = 1,338.25 × 638.50
  4. Step 4: Simplify right side
    970.19x = 854,462.74
  5. Step 5: Solve for x
    x = 854,462.74/970.19
  6. Step 6: Final answer
    x = 880.72

Related Problems

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Half scale
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Double scale
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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.