Finding the Fourth Proportional to 30.60, 42.12 and 27
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Solution
The fourth proportional to 30.60, 42.12 and 27 is: 37.16
Step by Step Solution
- Step 1: Write the proportion equation
30.60 : 42.12 = 27 : x - Step 2: Convert to fraction form
30.60/42.12 = 27/x - Step 3: Cross multiply
30.60x = 42.12 × 27 - Step 4: Simplify right side
30.60x = 1,137.24 - Step 5: Solve for x
x = 1,137.24/30.60 - Step 6: Final answer
x = 37.16
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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.