Finding the Fourth Proportional to 49.50, 74.28 and 21
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Solution
The fourth proportional to 49.50, 74.28 and 21 is: 31.51
Step by Step Solution
- Step 1: Write the proportion equation
49.50 : 74.28 = 21 : x - Step 2: Convert to fraction form
49.50/74.28 = 21/x - Step 3: Cross multiply
49.50x = 74.28 × 21 - Step 4: Simplify right side
49.50x = 1,559.88 - Step 5: Solve for x
x = 1,559.88/49.50 - Step 6: Final answer
x = 31.51
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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.