Finding the Fourth Proportional to 81.19, 121.10 and 70.93
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Solution
The fourth proportional to 81.19, 121.10 and 70.93 is: 105.80
Step by Step Solution
- Step 1: Write the proportion equation
81.19 : 121.10 = 70.93 : x - Step 2: Convert to fraction form
81.19/121.10 = 70.93/x - Step 3: Cross multiply
81.19x = 121.10 × 70.93 - Step 4: Simplify right side
81.19x = 8,589.62 - Step 5: Solve for x
x = 8,589.62/81.19 - Step 6: Final answer
x = 105.80
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.