TASK DEFINITION: The task is to generate the correct answer for a given math problem.
PROBLEM: Problem: a worker is paid a regular rate of rs . 30 for completing a survey . the worker completes 100 surveys per week . for any survey involving the use of her cellphone , she is paid at a rate of that is 20 % higher than her regular rate . if she completed 50 surveys involving the use of her cellphone , how much did she get that week ?

SOLUTION: 330

PROBLEM: Problem: the compound interest on $ 30,000 at 7 % p . a is $ . 4347 . find out the period ( in years ) ?

SOLUTION: 2

PROBLEM: Problem: by selling an article at rs . 500 , a profit of 25 % is made . find its cost price ?

SOLUTION:
400