Finding the Fourth Proportional to 40.57, 60.91 and 21.31
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Solution
The fourth proportional to 40.57, 60.91 and 21.31 is: 31.99
Step by Step Solution
- Step 1: Write the proportion equation
40.57 : 60.91 = 21.31 : x - Step 2: Convert to fraction form
40.57/60.91 = 21.31/x - Step 3: Cross multiply
40.57x = 60.91 × 21.31 - Step 4: Simplify right side
40.57x = 1,297.99 - Step 5: Solve for x
x = 1,297.99/40.57 - Step 6: Final answer
x = 31.99
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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.