Answer:
The average increase in the number of smart
phones per year is 45
Step-by-step explanation:
Given that :
Number of students who had phones in 2005 = 120
Number of students who had phones in 2010 = 345
(345 - 120) / 5
225 / 5
= 45
Hence, average increase in number of smartphones per year = 45
Answer:
140
Step-by-step explanation:
80 x 1.75 = 140
Answer:
2a + 4b = 44
a+b=15
Step-by-step explanation:
Call a the number of chickens, b the number of horses
We have: 2a + 4b = 44
a + b = 15
=> 2(a+b) = 30
<=> (2a + 4b) - (2a + 2b) = 14
2b = 14
=> b = 7
=> a = 8
So 8 chickens, 7 cows.