An alloy is to contain copper and zinc in the ratio 9:4.the zinc required to melt 24 kg of copper
Correct
here,copper:zinc=9x and 4x
then, 9x=24
x=24/9=8/3kg
so zinc=4x=4*8/3 kg =32/3 kg
Incorrect
here,copper:zinc=9x and 4x
then, 9x=24
x=24/9=8/3kg
so zinc=4x=4*8/3 kg =32/3 kg
Question 4 of 25
4. Question
1 points
two numbers are in the ratio 7:8.if 3 is added to each of them.their ratio becomes 8:9.the numbers are:
Correct
let the number be 7x and 8x
so,7x+3/8x+3=8/9
9(7x+3)=8(8x+3)
x=3
numbers are: 7x=7*3=21
8x=8*3=24
Incorrect
let the number be 7x and 8x
so,7x+3/8x+3=8/9
9(7x+3)=8(8x+3)
x=3
numbers are: 7x=7*3=21
8x=8*3=24
Question 5 of 25
5. Question
1 points
A box contains Rs 56 in the form of coins of the one rupee,50 paise and 25 paise.The number of 50 paise coin is double the number of 25 paise coins and 4 times the number of one rupee coins.The numbers of 50 paise coins in the box is:
Correct
let the number of 1 rupee coins be x,50 paise coins be 4x and 25 paise coins be 2x
so,x+4x/2+2x/4=56
4x+8x+2x=56*4
x=224/14=16
no of 50 paise coins is 4*16=64
Incorrect
let the number of 1 rupee coins be x,50 paise coins be 4x and 25 paise coins be 2x
so,x+4x/2+2x/4=56
4x+8x+2x=56*4
x=224/14=16
no of 50 paise coins is 4*16=64
Question 6 of 25
6. Question
1 points
8 people are planning to share equally the cost of a rental car.if 1 person withdraws from the arrangement and the others share equally entire cost of the car,then the share of each of the remaining persons increased by:
Correct
when no of people=8
then,share of each person=1/8 of the total cost
when no of people=7
then,share of each person=1/7 of the total cost
increase in the share of a person=1/7-1/8=1/56
1/7 0f 1/8,i.e.1/7 of the original share of each person.
Incorrect
when no of people=8
then,share of each person=1/8 of the total cost
when no of people=7
then,share of each person=1/7 of the total cost
increase in the share of a person=1/7-1/8=1/56
1/7 0f 1/8,i.e.1/7 of the original share of each person.
Question 7 of 25
7. Question
1 points
A bag contains Rs 187 in the form of 1 rupee,50 paise and 10 paise coins in the ratio 3:4:5.find the number of each type of coins
Correct
let the no of coins be 3x,4x and 5x
then,3x+4x/2+5x/10=187
30x+20x+5x=187*10
x=1870/55=34
no of coins: 1 rupee=3x=3*34=102
50 paise=4x=4*34=136
10 paise=5x=5*34=170
Incorrect
let the no of coins be 3x,4x and 5x
then,3x+4x/2+5x/10=187
30x+20x+5x=187*10
x=1870/55=34
no of coins: 1 rupee=3x=3*34=102
50 paise=4x=4*34=136
10 paise=5x=5*34=170
Question 8 of 25
8. Question
1 points
Ratio of earnings of A and B is 4:7.if the earnings of A increase by 50% and those of B decrease by 25%.the new ratio of their earning becomes 8:7.what is A’s earning?
Correct
let the earning of A and B=4x and 7x.
new earning of A=4*150%=6x
new earning of B=7*75%=5.25x
then, 6x/5.25x=8/7
so,the data is inadequate
Incorrect
let the earning of A and B=4x and 7x.
new earning of A=4*150%=6x
new earning of B=7*75%=5.25x
then, 6x/5.25x=8/7
so,the data is inadequate
Question 9 of 25
9. Question
1 points
P,Q and R there cities.the ratio of average temperature between P and Q is 11:12 and P and R is 9:8.the ratio between the average temperature of Q and R is:
Correct
P/Q=11/12 and P/R=9/8
P/Q=11×9/12×9=99/108 and P/R=9×11/8×11=99/88
then,Q/R=108/88=27/22
so,Q:R=27:22
Incorrect
P/Q=11/12 and P/R=9/8
P/Q=11×9/12×9=99/108 and P/R=9×11/8×11=99/88
then,Q/R=108/88=27/22
so,Q:R=27:22
Question 10 of 25
10. Question
1 points
Rs 407 are to be divided among A,B and C so that their shares are in the ratio 1/4:1/5:1/6.the shares of A,B,c are:
Correct
here,A:B:C=1/4:1/5:1/6=15:12:10/60=15:12:10
A’s share =407*15/37=Rs165
B’s share =407*12/37=Rs132
C’s share =407*10/37=Rs110
Incorrect
here,A:B:C=1/4:1/5:1/6=15:12:10/60=15:12:10
A’s share =407*15/37=Rs165
B’s share =407*12/37=Rs132
C’s share =407*10/37=Rs110
Question 11 of 25
11. Question
1 points
The income of A and B are in the ratio 3:2 and their expenditure in the ratio 5:3.if each saves Rs1500,then B’s income is
Correct
let the income of A and B be 3x and 2x
expenditure of A and B be 5y and 3y
then, 3x-5y=1500……….(i)
2x-3y=1500………..(ii)
by solving i and ii we get
x=3000 and y=1500
hence,B’s income = 2x=2*3000=Rs6000
Incorrect
let the income of A and B be 3x and 2x
expenditure of A and B be 5y and 3y
then, 3x-5y=1500……….(i)
2x-3y=1500………..(ii)
by solving i and ii we get
x=3000 and y=1500
hence,B’s income = 2x=2*3000=Rs6000
Question 12 of 25
12. Question
1 points
in 40 liters mixture glycerine and water are in the ratio of 3:1.the quantity of water added in the mixture in in order to make this ratio 2:1 is
Correct
Qty of glycerine = 40 x 3/4=30 liters
Qty of water = 40×1/4=10 liters
then,total qty of mixture=40+X liters
total qty of water = 10+X liters
so,30/10+X=2/1
X=5 liters of water must be added to the mixture
Incorrect
Qty of glycerine = 40 x 3/4=30 liters
Qty of water = 40×1/4=10 liters
then,total qty of mixture=40+X liters
total qty of water = 10+X liters
so,30/10+X=2/1
X=5 liters of water must be added to the mixture
Question 13 of 25
13. Question
1 points
log 144=
Correct
log 144 = log(16×9)=log 16+log 9 =4 log 2+2 log 3
Incorrect
log 144 = log(16×9)=log 16+log 9 =4 log 2+2 log 3
Question 14 of 25
14. Question
1 points
in what ratio should tea worth rs 10 per kg mixed with tea worth rs 14 per kg, so, that the average price of the mixture may be rs 11 per kg?
Correct
let X be qty of tea worth rs 10 per kg
Y be qty of tea worth 14 rs per kg
total , price of the mixture = 10X+14Y and qty of mixture=X+Y
average price=10X+14Y/X+Y=11
10X+14Y=11X+11Y
3Y=X
X/Y=3/1=3:1
Incorrect
let X be qty of tea worth rs 10 per kg
Y be qty of tea worth 14 rs per kg
total , price of the mixture = 10X+14Y and qty of mixture=X+Y
average price=10X+14Y/X+Y=11
10X+14Y=11X+11Y
3Y=X
X/Y=3/1=3:1
Question 15 of 25
15. Question
1 points
two presons are in the ratio of 5:7. 18 yr ago there ages were in the ratio of 8:13, there present ages are
Correct
let present ages of person be 5X and 7X
18yr ago, there ages =5X-18 and 7X-18
then,5X-18/7X-18=8/13
65X-234=56X-144
X=10
there present ages are 5X = 5×10=50 yr and 7X =7×10=70
Incorrect
let present ages of person be 5X and 7X
18yr ago, there ages =5X-18 and 7X-18
then,5X-18/7X-18=8/13
65X-234=56X-144
X=10
there present ages are 5X = 5×10=50 yr and 7X =7×10=70
Question 16 of 25
16. Question
1 points
if A,B and C started a business by investing rs 126000, rs 84000 and rs 210000.if at the end of the year profit is rs 242000 then the share of each is
Correct
given, A:B:C=126000:84000:210000=126:84:210=3:2:5 and profit = rs 242000
A’s share = 3/10×242000=72600
B’s share = 2/10×242000=48400
C’s share = 5/10×242000=121000
Incorrect
given, A:B:C=126000:84000:210000=126:84:210=3:2:5 and profit = rs 242000
4th proportional to x,2x,(x+1) is (2x+2) i.e,x:2x::(x+1):(2x+2)
Incorrect
let 4th proportional be x,2x and (x+1) be t
then,x/2x=x+1/t
1/2=x+t/t
t=2x+2
4th proportional to x,2x,(x+1) is (2x+2) i.e,x:2x::(x+1):(2x+2)
Question 19 of 25
19. Question
1 points
log(m+n)=log m + log n,m can be expressed as
Correct
log(m+n)=log m + log n
log(m+n)=log(mn)
taking antilog on both side
antilog [log(m+n)]=antilog [log(mn)]
m+n=mn
mn-m=n
m(n-1)=n
m=n/n-1
Incorrect
log(m+n)=log m + log n
log(m+n)=log(mn)
taking antilog on both side
antilog [log(m+n)]=antilog [log(mn)]
m+n=mn
mn-m=n
m(n-1)=n
m=n/n-1
Question 20 of 25
20. Question
1 points
what must be added to each term of the ratio 49:68, so that it becomes 3:4?
Correct
let the number added be x
49+x/68+x=3/4
196+4x=204+3x
x=8
Incorrect
let the number added be x
49+x/68+x=3/4
196+4x=204+3x
x=8
Question 21 of 25
21. Question
1 points
The students of 2 classes are in the ratio of 5:7.if 10 students left from each class,then the remaining students are in the ratio of 4:6 then the number of students in each class is
Correct
let the ratio be 5x:7x
if 10 students left,ratio becomes 4:6
5x-10/7x-10=4/6
30x-60=28x-40
2x=20
x=10
no of students in each class is 5x and 7x i.e.50 and 70
Incorrect
let the ratio be 5x:7x
if 10 students left,ratio becomes 4:6
5x-10/7x-10=4/6
30x-60=28x-40
2x=20
x=10
no of students in each class is 5x and 7x i.e.50 and 70
Question 22 of 25
22. Question
1 points
The recurring decimal 2.7777…… can be expressed as