Finding the Fourth Proportional to 1,210, 1,669.80 and 658
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Solution
The fourth proportional to 1,210, 1,669.80 and 658 is: 908.04
Step by Step Solution
- Step 1: Write the proportion equation
1,210 : 1,669.80 = 658 : x - Step 2: Convert to fraction form
1,210/1,669.80 = 658/x - Step 3: Cross multiply
1,210x = 1,669.80 × 658 - Step 4: Simplify right side
1,210x = 1,098,728.40 - Step 5: Solve for x
x = 1,098,728.40/1,210 - Step 6: Final answer
x = 908.04
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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.