Finding the Fourth Proportional to 1,947, 2,920.50 and 579
Calculator
Solution
The fourth proportional to 1,947, 2,920.50 and 579 is: 868.50
Step by Step Solution
- Step 1: Write the proportion equation
1,947 : 2,920.50 = 579 : x - Step 2: Convert to fraction form
1,947/2,920.50 = 579/x - Step 3: Cross multiply
1,947x = 2,920.50 × 579 - Step 4: Simplify right side
1,947x = 1,690,969.50 - Step 5: Solve for x
x = 1,690,969.50/1,947 - Step 6: Final answer
x = 868.50
Related Problems
Find fourth proportional to 973.50, 1,460.25 and 289.50
Half scale
Find fourth proportional to 3,894, 5,841 and 1,158
Double scale
Find fourth proportional to 1,948, 2,922 and 580
Similar ratio
Find fourth proportional to 2,920.50, 4,380.75 and 868.50
1.5x scale
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.