how to sum the concatenated fileds in abap?

hi sir,

I need to sum the concatenate field in abap,please guide me to solve the problem.

example:data:lv_text1 type char,

                     lv_text2 type char,

                     lv_text3 type char.

lv_text1 = 100.00.

lv-text1 = 20.00

lv_text2 = 30.00 .

lv_text2 = 40.00.

concatenate lv_text1 lv_text2 into lv_tesx3.

i have concatenate those two fields but i need  to sum on those fields.

the output format should be

lv_text1       lv_text2

120.00        70.00 . in lv_text3.

thanks.

ravi.