instruction:
The task is to generate the correct answer for a given math problem.
question:
Problem: a can do a work in 15 days and b in 20 days . if they work on it together for 7 days , then the fraction of the work that is left is
answer:
11 / 6


question:
Problem: the ratio of the radius of two circles is 1 : 3 , and then the ratio of their areas is ?
answer:
1 : 9


question:
Problem: given that 268 * 74 = 19832 , find the values of 2.68 * 0.74 .
answer:

1.9832