2a
33
+ b9
____
99
If a and b represent positive single digits in the correctly worked computation above, what is the value of a + 3b ?
Choices
A) 2 B) 7 C) 9 D) 11 E) 12
Adding the digits in unit's place , a+ 3 + 9 = 19 (Since a and b are positive single digits )   =&gt; a = 7   Now adding the digits in ten's place , 2+ 3 + b + 1= 9 (1 has been carried over from nit's place addition)   =&gt; b= 3   a+3b = 2+2*3   =11   Answer 11
<result>D</result>
2a
33
+ b9
____
99
If a and b represent positive single digits in the correctly worked computation above, what is the value of a + 3b ?