Finding the Fourth Proportional to 81.51, 122.91 and 69.63
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Solution
The fourth proportional to 81.51, 122.91 and 69.63 is: 105.00
Step by Step Solution
- Step 1: Write the proportion equation
81.51 : 122.91 = 69.63 : x - Step 2: Convert to fraction form
81.51/122.91 = 69.63/x - Step 3: Cross multiply
81.51x = 122.91 × 69.63 - Step 4: Simplify right side
81.51x = 8,558.22 - Step 5: Solve for x
x = 8,558.22/81.51 - Step 6: Final answer
x = 105.00
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Why These Related Problems?
These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.