Finding the Fourth Proportional to 81.14, 121.80 and 69.08
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Solution
The fourth proportional to 81.14, 121.80 and 69.08 is: 103.70
Step by Step Solution
- Step 1: Write the proportion equation
81.14 : 121.80 = 69.08 : x - Step 2: Convert to fraction form
81.14/121.80 = 69.08/x - Step 3: Cross multiply
81.14x = 121.80 × 69.08 - Step 4: Simplify right side
81.14x = 8,413.94 - Step 5: Solve for x
x = 8,413.94/81.14 - Step 6: Final answer
x = 103.70
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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.