24kmph
time taken = x/40 + 2x/20
=> x=8
so, 3x = 24
M
M. L
L
2
Take one screw out from the rest of the three tyres and put the screws in the fourth tyre. Now all tyres will be held by three screws each.
1500
Ans :15
X be a present age of mudit
After 18 year age of mudit is X+18
4 year ago age was X-4
As per question,
X+18=3(X-4)
X+18=3X-12
3X-X=18+12
2X=30
X=15
450÷100×30=135
450-135=315
Ans: 315
3, 8, 15, 24, 34, 48, 63
8-3 = 5
15-8 = 7
24-15 = 9
34-24 = 10 this one should be 35-24 = 11
48 – 34 = 14 based on the correction will be 48-35 = 13
63-48 = 15
the difference will create a series 5,7,9,11,13,15…..etc
let first digit be ‘X’
then 5th digit is ‘3X’
let 2nd digit be ‘Y’
then 3rd digit is ‘Y-3’
and 4th digit is ‘Y+4’
then the no is ‘(X)(Y)(Y-3)(Y+4)(3X)’
from the above we can say 3X<=9
so X<=3 and any of the digit in the number is <=9
and also given that 3 pairs sum is 11...
so make trial and error..
if X=1...any of the no is 10 which is wrong trial....
if X=2...then let Y+4=9 ==> Y=5
then no is 25296
first pair 2+9=11
second pair 2+9=11
third pair 5+6=11
now the answer is 25296
When none of the digits are repeated:
The hundred’s place can be filled by any of the digits: 2, 3, 5, 6, 7 or 8 except the one which has already been used at the thousand’s place, so it can be filled in 5 ways.
Similarly tens’ place can be filled in 4 ways: only those 4 numbers which have not been use either at hundred’s or thousand’s place.
Unit’s place can be filled in only 3 ways. So, total number of nos. Possible =4×5×4×3= 240
None
In the example first we have to find the area of the field
we have given the following values ,
cost of fencing per meter = Rs 1.50
Diameter of circular field = 28
We have to find the area , a = ?
We know that,
Area = 2 π r
= 2 x 22/7 x 14
= 2 x 22 x 2
= 44 x 2
= 88 sq. m
So, area of circle is 88 sq.m
Now just multiply it with 1.50
cost of fencing = 88 x 1.50
= Rs. 132
So, the cost of fencing the circular field is Rs. 132
mother
Let the number be x.
So x-2 =15/x, or
x^2–2x-15=0, or
(x-5)(x+3)=0
Hence x = 5 or -3.
Check: When x=5, 5–2=3 which is 15/5=3.
When x=-3, -3–2=-5 which is 15/-3=-5.
The number is 5 or -3.