Hi, One of the solution is as follow:
select cust.customer_id,fname,mname,lname,e_mail,credit.tot_credit+coupan.tot_coup no_of_recharge,

credit.tot_credit_val+coupan.tot_coup_val tot_recharging,tot_trans,credit.tot_credit_val+coupan.tot_coup_val-current_balance transaction_val,cust.current_balance

from Customer cust ,

(select customer_id,count(value) tot_credit,sum(value) tot_credit_val from credit_card group by customer_id) credit,

(select customer_id,count(value) tot_coup,sum(value) tot_coup_val from coupan group by coupan.customer_id) coupan

where coupan.customer_id=cust.customer_id and cust.customer_id=credit.customer_id;