100% of 350 is 350.
What you need to do is find 26% of 350, and add it to 350 (100%).
To accomplish that, change 26% to a decimal by moving the decimal point two places to the left. 26% = 0.26
Next, multiply 350 by 0.26
350 • 0.26 = 91
Finally, just add 350 and 91 to get 126%
350 + 91 = 441
126% of 350 = 441