Finding the Fourth Proportional to 42,965.80, 64,451.77 and 17,980.69

Step by Step Solution

1. Step 1: Write the proportion equation
   42,965.80 : 64,451.77 = 17,980.69 : x
2. Step 2: Convert to fraction form
   42,965.80/64,451.77 = 17,980.69/x
3. Step 3: Cross multiply
   42,965.80x = 64,451.77 × 17,980.69
4. Step 4: Simplify right side
   42,965.80x = 1,158,887,296.32
5. Step 5: Solve for x
   x = 1,158,887,296.32/42,965.80
6. Step 6: Final answer
   x = 26,972.32