Answer:
Step-by-step explanation:

Answer:
21 is common denominator.
15 and 7 are the corresponding numberators.
Step-by-step explanation:
You multiply the 7 and 6, then apply to the fractions, and slowly reduce until you find a good match.
2
350
x 40
____
000
1400
____
1,400
one tip:
Example: 4 - (-3)
it instantly becomes positive because the negatives are close to each other as shown.
hope that helps :)