Finding the Fourth Proportional to 75.19, 112.79 and 21.09
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Solution
The fourth proportional to 75.19, 112.79 and 21.09 is: 31.64
Step by Step Solution
- Step 1: Write the proportion equation
75.19 : 112.79 = 21.09 : x - Step 2: Convert to fraction form
75.19/112.79 = 21.09/x - Step 3: Cross multiply
75.19x = 112.79 × 21.09 - Step 4: Simplify right side
75.19x = 2,378.74 - Step 5: Solve for x
x = 2,378.74/75.19 - Step 6: Final answer
x = 31.64
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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.