Answer:
"Dominic lived in Spain for 13 months and Columbia for 7 months."
Step-by-step explanation:
let months stayed in spain be "s" and months stayed in columbia be "c"
We can write 2 equations.
Since, lived in Spain and Columbia for a total of 20 months, we can write:
s + c = 20
Also, since 120 words per month in Spain and 150 words per month in Columbia for a total of 2610 new words, we can write:
120s + 150c=2610
Solving first for s:
s = 20 - c
Putting in 2nd and solving:
120(20 - c) + 150c = 2610
2400 - 120c + 150c = 2610
30c = 210
c = 7
Now,
s = 20 - c = 20 - 7 = 13
So
"Dominic lived in Spain for 13 months and Columbia for 7 months."