SAT Math: More “Picking Numbers” Problems

If you’ve read my recent post on Picking Numbers and you’re looking to try a few more problems on this very important SAT Math strategy, check out these problems. You may see a way to solve the problem that doesn’t involve picking numbers and that’s great!  If it seems easier to you to actually “do the math,” then go for it.  But for each of these problems, picking numbers can be used as a strategy to get the correct answer.  The solutions appear at the bottom of this post.

1)  If a is an odd integer and b is an even integer, which of the following must be even?

(A)  ab –  1
(B)  ab + 1
(C)  (a + b)2
(D)  a2 + b + 1

(E)  b + 2

2)  If x is a multiple of 6 and y is a multiple of 5, which of the following must be a multiple of 3?

(A)  x2 + 4y
(B)  4x + 3y
(C)  xy + 1

(D)  xy + 5
(E)  (x + y)2  

3)  In the diagram below, what is the value of c (in degrees) in terms of a and b?

Determine the Value of c

(A)  ab – 180
(B)  2a + 2b – 180
(C)  180 – a + b
(D)  360 – 2a – 2b
(E)  360 – 2a – 4b

 4)  For the two functions defined below, which of the following is equivalent to f(a + 1)?

f(n) = n2 + n
g(n) = n2 + 3n + 5

(A)  g(a)
(B)  g(a + 1)
(C)  g(a) – 3
(D) g(a) – 1
(E)  g(a) + 1

5)  After the first term, each term in a sequence is found by adding 3 to twice the previous term.  If the first term of the sequence is n and n ≠ 0, what is the average (arithmetic mean) of the second and third terms?

(A)  2n + 3
(B)  2n + 6
(C)  3n + 6
(D)  4n + 6
(E)  6n + 12

If you have questions about these problems, the “Picking Numbers” strategy, or anything else to do with the SAT, leave a comment or send me an email at info@cardinalec.com .

Solutions:

1)  (D)
2)  (B)
3)  (E)
4)  (C)
5)  (C)

 

 

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