@krum said:For how many integers 'm' is m^3-8m^2+20m-13 a prime number ?
m=1
(m-1)*(m^2-7m+13)
It can be break into two factors.
0
@Hypertexter said:Q. There were 90 questions in an exam. If one mark was awarded for every correct answer and 1/3rd deducted for every wrong answer, how many different net scores were possible in the exam?A. 120 B. 358C. 359D. 360
270-(-90)+1-3=358
@gautam22 said:A tank of ht. 3h has and inlet pipe A and two outlet pipes B and C at heights 2h and h from the base.A can fill tank in 12 hrs. The time in which B and C can empty it are in the ratio 1:2. All the pipes are opened simultaneously. The tank is filled in 16 hrs 48 mins. Find the time in which B can empty it?24273036
Let total volume be 36
Efficiency of A be 36/12=3units per hour
Efficiency of B be 12/x =12/x units per hour
Efficiency of C be 12/x units per hour
36/(3-24/x)=84/5
180=264-24*84/(x)
x=24
@19rsb said:S=(1x997) + (2x996) + (3x995) + (4x994) +.............+(996x2) + (997x1)S=997 x 499 x A, then what is the sum of the digits of A?
A=333
Sum=9
Sum=9
A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
@catter2011 said:A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
6?
@catter2011 said:A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
(3^10-6^24+7^50-2^99)mod25
3^10mod25
=3*(27)^3mod25
=3*8mod25
=-1
2^99mod25
=2^9*(1024)^9mod25
=2^9*-1mod25
=-12 or 13
6^24mod25
=(11)^12mod25
=(-4)^6mod25
=16*6mod25
=-4 or 21
7^50mod25
=-1 or 24
==>-1+4-1+12=14
14/25=0.56
b=6
3^10mod25
=3*(27)^3mod25
=3*8mod25
=-1
2^99mod25
=2^9*(1024)^9mod25
=2^9*-1mod25
=-12 or 13
6^24mod25
=(11)^12mod25
=(-4)^6mod25
=16*6mod25
=-4 or 21
7^50mod25
=-1 or 24
==>-1+4-1+12=14
14/25=0.56
b=6
@catter2011 said:A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
Edit:6
In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?
18
19
20
21
18
19
20
21
@catter2011 said:A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
6?
@catter2011 said:A number N when divided by 25 gives a result, with the fractional part of the form 0.ab. What is b if N=(3^10-6^24+7^50-2^99) ?
3^10-6^24+7^50-2^99 mod 25
=-11 mod 25
=14 mod 25
=.56
==> b=6
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
18
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
18?
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
maximum age of the boy can be 8
so, 18
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
x+x+38+y+y+26=82
=>x+y=9
x=8,y=1
=>0+38+19=57
18
=>x+y=9
x=8,y=1
=>0+38+19=57
18
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
18
@catter2011 said:In a family, there are four members. the father is of 38 years older than his son, and the mother is 26 years older than her daughter. The sum of their ages today is 82. All members are at least one year old. Eight years ago, the sum of their ages was 57. Which of these is a possible value for the age of the son in 10 years ?18192021
18
How many values of n satisfy the equation, if n is an integer and x is a natural no.
n+n^2+5n = n^x
1)1
2)2
3)0
4)More than 3
@maddy2807 said:How many values of n satisfy the equation, if n is an integer and x is a natural no.n+n^2+5n = n^x1)12)23)04)More than 3
4) ??
@maddy2807 said:How many values of n satisfy the equation, if n is an integer and x is a natural no.n+n^2+5n = n^x1)12)23)04)More than 3
2,3,-2 and -3 satisfy the equation..so answer is option 4?
Many other values may also satisfy