What is the product of 1 and 1 3rd and 7/10

The correct answer is 14/15. To answer this problem, it would help to change the mixed number into an improper fraction.

1 1/3
4/3   Multiply 3 by 1, and then add 1 and put 4 over 3.

4/3 x 7/10   Now, multiply both numbers by each other. Since we're multiplying, we don't need to find a least common denominator.
28/30   4 x 7 = 28; 3 x 10 = 30
14/15   Since 28 and 30 are divisible by 2, we need to simplify the answer.

The correct answer is 14/15.

Hope this helps!