Search found 11 matches


Re: Difficult Math Question #32 - Sets

A set of numbers has the property that for any number t in the set, t + 2 is in the set. If –1 is in the set, which of the following must also be in the set?
I. –3 II. 1 III. 5
A. I only
B. II only
C. I and II only
D. II and III only
E. I, II, and III

by jasminekaur280

Wed Jun 03, 2020 12:41 am
Forum: Problem Solving
Topic: Difficult Math Question #32 - Sets
Replies: 6
Views: 4545

Re: Difficult Math Question #67 - Combinations

There are 10 TV sets; we have to choose 4 at a time. So we can do that by 10C4 ways. We have 7 good TV’s and 3 defective. Now we have to choose 4 TV sets with at least 2 defective. We can do that by 2 defective 2 good 3 defective 1 good That stands to 3C2*7C2 + 3C3*7C1 (shows the count) If they had ...

by jasminekaur280

Wed Jun 03, 2020 12:33 am
Forum: Problem Solving
Topic: Difficult Math Question #67 - Combinations
Replies: 5
Views: 4360

Re: Difficult Math Problem #72 - Number Theory

Write down n x (2^5) x (6^2) x (7^3) as
= n x (2^5) x (3^2) x (2^2) x (7^3),
= n x (2^7) x (3^2) x (7^3)

now at a minimum 5^2 and a 3 is missing from this to make it completely divisible by 5^2 x 3^3

Hence answer = 5^2 x 3 = 75

by jasminekaur280

Wed Jun 03, 2020 12:30 am
Forum: Problem Solving
Topic: Difficult Math Problem #72 - Number Theory
Replies: 3
Views: 3942

Re: Difficult Math Problem #73 - Arithmetic, Number Theory

Consider 5 15 25 ... 995 l = a + (n-1)*d l = 995 = last term a = 5 = first term d = 10 = difference 995 = 5 + (n-1)*10 thus n = 100 = # of terms consider 5 10 15 20.... 995 995 = 5 + (n-1)*5 => n = 199 Another approach... Just add up 995 + 985 + 975 + 965 + 955 + 945 = 5820, so it has to be greater ...

by jasminekaur280

Wed Jun 03, 2020 12:29 am
Forum: Problem Solving
Topic: Difficult Math Problem #73 - Arithmetic, Number Theory
Replies: 3
Views: 9104

Re: Difficult Math Problem #75 - Probability

The probability of an event A occurring is the number of outcomes that result in A divided by the total number of possible outcomes. There is only one result that results in a win: receiving three aces. Since the order of arrangement does not matter, the number of possible ways to receive 3 cards is...

by jasminekaur280

Wed Jun 03, 2020 12:27 am
Forum: Problem Solving
Topic: Difficult Math Problem #75 - Probability
Replies: 6
Views: 4520

Re: The price of gasoline at a service station increased from $1.65 per gallon last week to $1.82 per gallon this week.

For every gallon of gas bought, the price at T2 (second week) will be $0.17 more (1.82-1.65). For every dollar spent, the price at T2 will be 0.17/1.65 more -> we are essentially finding the percentage increase (p2-p1/p1). The amount spent at T1 = 26.4 => She would have spent (26.4 * 0.17)/1.65 The ...


Re: Distance/Rate Problems

A = original speed
B = A + 16
Average speed = 30mph

Average speed = 2*A*B / A+B

=> 30 = 2 * A(A+16) / 2A+16
30=2(A^2 + 16A) / 2(A+8)
30=A^2 + 16A / A+8

30A + 240 = A^2 + 16A
A^2 - 14A -240 = 0
(A-24)(A+10) = 0
=> A = 24 as it cannot be negative. Answer is D

by jasminekaur280

Tue Jun 02, 2020 5:12 am
Forum: Problem Solving
Topic: Distance/Rate Problems
Replies: 3
Views: 462

Re: A factory has 500 workers, 15 percent of whom are women. If 50 additional workers are to be hired and all of the pre

Currently, we have 0.15 x 500 = 75 female employees. If we let n = the number of additional female employees hired, we can create the equation:

(75 + n)/(500 + 50) = 20/100

(75 + n)/550 = 1/5

5(75 + n) = 550

375 + 5n = 550

5n = 175

n = 35

Answer: E


Re: A factory has 500 workers, 15 percent of whom are women. If 50 additional workers are to be hired and all of the pre

Currently, we have 0.15 x 500 = 75 female employees. If we let n = the number of additional female employees hired, we can create the equation:

(75 + n)/(500 + 50) = 20/100

(75 + n)/550 = 1/5

5(75 + n) = 550

375 + 5n = 550

5n = 175

n = 35

Answer: E


Re: Sixty percent of the members of a study group are women, and 45 percent of those women are lawyers. If one member of

We can assume that the total number of people is 100.
If 60% of them are females, total number of females= 60
45% of females are lawyers, No. of female lawyers= 45% of 60=> 27
Probability of selecting female lawyer = 27/100 => 0.27
ANSWER= C


Re: Fractions/Ratios/Decimals

With the information given to us, let’s say there are 5x right and 3x left sided mirrors.

Number of mirrors left = 5x – 3x = 2x

2x = 30 => x = 15

Hence, there are a total of 5x + 3x = 8x = 8*15 = 120 mirrors.

Therefore the correct answer is B

by jasminekaur280

Mon Jun 01, 2020 6:20 am
Forum: Problem Solving
Topic: Fractions/Ratios/Decimals
Replies: 3
Views: 473