Well, you already have the decay model, so just plug that in
Answer:
Jessica spent 10 months in Spain and 8 months in Colombia.
Step-by-step explanation:
Let x be the number of months Jessica lived in Spain, then she lived 18 - x months in Colombia.
She learned an average of 160 words per month when she lived in Spain, so she learned 160x words in Spain.
She learned an average of 200 words per month when she lived in Colombia, so she learned 200(18-x) words in Colombia.
In total, she learned a total of 3,200 new words, thus

Jessica spent 10 months in Spain and 8 months in Colombia.
I know the answer for two.All you do is 9 times 3 times 2
3 7/8 because looking at the ruler, the line is 7 of the 8. hope that’s helps!
Answer:
X = 7
Step-by-step explanation:
I really don’t know