Finding the Fourth Proportional to 77.21, 115.73 and 25.80
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Solution
The fourth proportional to 77.21, 115.73 and 25.80 is: 38.67
Step by Step Solution
- Step 1: Write the proportion equation
77.21 : 115.73 = 25.80 : x - Step 2: Convert to fraction form
77.21/115.73 = 25.80/x - Step 3: Cross multiply
77.21x = 115.73 × 25.80 - Step 4: Simplify right side
77.21x = 2,985.71 - Step 5: Solve for x
x = 2,985.71/77.21 - Step 6: Final answer
x = 38.67
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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.