Finding the Fourth Proportional to 84.21, 115.95 and 74.49
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Solution
The fourth proportional to 84.21, 115.95 and 74.49 is: 102.57
Step by Step Solution
- Step 1: Write the proportion equation
84.21 : 115.95 = 74.49 : x - Step 2: Convert to fraction form
84.21/115.95 = 74.49/x - Step 3: Cross multiply
84.21x = 115.95 × 74.49 - Step 4: Simplify right side
84.21x = 8,637.12 - Step 5: Solve for x
x = 8,637.12/84.21 - Step 6: Final answer
x = 102.57
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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.