Problem Solving

Pros, Excuse me if my questions are trivial !

1) Grace has 16 stones in her pocket. She has 8 red ones, 4 green ones, and 4 blue ones. What is the minimum number of stones she must take out of her pocket to ensure that she has one of each color?

choices:
4
8
12
13
16

2) A student receives his grade report from a local community college, but the GPA is smudged. He took the following classes: a 2 hour credit art, a 3 hour credit history, a 4 hour credit science course, a 3 hour credit mathematics course, and a 1 hour science lab. He received a “B” in the art class, an “A” in the history class, a “C” in the science class, a “B” in the mathematics class, and an “A” in the science lab. What was his GPA if the letter grades are based on a 4 point scale? (A=4, B=3, C=2, D=1, F=0)

choices:
2.7
2.8
3.0
3.1
3.2

3) Simon arrived at work at 8:15 A.M. and left work at 10: 30 P.M. If Simon gets paid by the hour at a rate of $10 and time and ½ for any hours worked over 8 in a day. How much did Simon get paid?

choices:
$120.25
$160.75
$173.75
$180
$182.50


Answers with explanations?

Thanks

S Vijay

Will sure do likewise from now on

Hi S Vijay,

1) Grace must take out n-1 stones for her to ensure that only one of each color is left, thus
RED -> 8-1 = 7 stones must be taken out.
GREEN -> 4-1 = 3 stones
BLUE -> 4-1 = 3 stones

In order for her to know that she has minimum one of each color the total number of stones taken out should be -> 7+3+3 = 13.

Therefore (D) is the correct choice.

2) Here is how to solve it

Course | Hours | Grade | Grade Points
Art 2 B=3 2*3 = 6
History 3 A=4 3*4 = 12
Science 4 C = 2 4*2 = 8
Maths 3 B = 3 3 * 3 = 9
Science Lab 1 A = 4 1 * 4 = 4

So Total Credit Hours = 13
Total Grade Points = 39

So GPA = 39/13 = 3.0

So (C) is correct.

3) Simon worked for 10:30 PM - 8:15 AM = 14 Hrs 15 min = 14.25 Hrs

The q says that simon gets paid 10$ per hour for 8 hours and
(time and 1/2) means 1.5 time 10$ (which is 15$) for any hours above that.

So for 8 hours -> 8 * 10$ = 80$
For rest hours -> (14.25-8) * 15$ = 6.25 * 15$ = 93.75$

So total he got 80 + 93.75 = 173.75$

which is choice (C)

I hope the explanation helps.

PS: Somebody really should support me on answer of 1 as I'm not toooo sure.

Yeah your answers are right and the explanations apt.

Thanks