Finding the Third Proportional to 12,990,240 and 19,791,768

Step by Step Solution

1. Step 1: Write the proportion equation
   12,990,240 : 19,791,768 = 19,791,768 : x
2. Step 2: Convert to fraction form
   12,990,240/19,791,768 = 19,791,768/x
3. Step 3: Cross multiply
   12,990,240x = 19,791,768 × 19,791,768
4. Step 4: Simplify right side
   12,990,240x = 391,714,080,565,824
5. Step 5: Solve for x
   x = 391,714,080,565,824/12,990,240
6. Step 6: Final answer
   x = 30,154,491.42