Finding the Fourth Proportional to 128.32, 177.09 and 79.19
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Solution
The fourth proportional to 128.32, 177.09 and 79.19 is: 109.29
Step by Step Solution
- Step 1: Write the proportion equation
128.32 : 177.09 = 79.19 : x - Step 2: Convert to fraction form
128.32/177.09 = 79.19/x - Step 3: Cross multiply
128.32x = 177.09 × 79.19 - Step 4: Simplify right side
128.32x = 14,023.24 - Step 5: Solve for x
x = 14,023.24/128.32 - Step 6: Final answer
x = 109.29
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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.