12 pigs×4 legs=48 legs
18 chickens×2 legs=36 legs
48 legs+36 legs=84 legs
12 are pigs and 18 are chickens
Answer:
we need to prove : for every integer n>1, the number
is a multiple of 5.
1) check divisibility for n=1,
(divisible)
2) Assume that
is divisible by 5, 
3) Induction,



Now, 



Take out the common factor,
(divisible by 5)
add both the sides by f(k)

We have proved that difference between
and
is divisible by 5.
so, our assumption in step 2 is correct.
Since
is divisible by 5, then
must be divisible by 5 since we are taking the sum of 2 terms that are divisible by 5.
Therefore, for every integer n>1, the number
is a multiple of 5.
Direct variation means that changes in x will result to changes in y. If x increase, y also increases and vice versa.
y = kx
k = y / x
y = 45 ; x = 40
k = 45/40
k = 1.125
y = 1.125x
y will increase by 1.125 interval of x.
Answer:
18
Step-by-step explanation: