1.220 + 1.450 = (a)  

1.510 + 1.140 = (a)  

2.430 + 1.140 = (a)  

2.740 + 2.030 = (a)  

3.213 + 2.000 = (a)  

3.341 + 2.155 = (a)  

3.624 + 3.214 = (a)  

4.206 + 3.131 = (a)  

5.523 + 2.335 = (a)