Finding the Fourth Proportional to 1,425, 2,137.86 and 399
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Solution
The fourth proportional to 1,425, 2,137.86 and 399 is: 598.60
Step by Step Solution
- Step 1: Write the proportion equation
1,425 : 2,137.86 = 399 : x - Step 2: Convert to fraction form
1,425/2,137.86 = 399/x - Step 3: Cross multiply
1,425x = 2,137.86 × 399 - Step 4: Simplify right side
1,425x = 853,006.14 - Step 5: Solve for x
x = 853,006.14/1,425 - Step 6: Final answer
x = 598.60
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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.