Quantitative Aptitude - Arithmetic Ability Questions

Given teacher drinks 9 ltr
Let number of boys be 'A'.
Let number of girls be 'B'.
Boy drinks 7 ltr and girl drinks 4 ltr
After class total water consumed = 42 ltr
Then,
9 + 7A + 4B = 42
=> 7A + 4B = 33
By trial and error method,
The only integers which satisfy the equation is A = 3 and B = 3
Therefore, number of girls in the class = 3.

B runs 35 m in 7 sec.

 B covers 200 m in (7/35*200) = 40sec

B's time over the course = 40 sec.

 A's time over the course (40 - 7) sec = 33 sec.

Cash price = $3695

Deposit =1/3 of $3695 = $1231.67

Loan amount = $3695.00 − $1231.67 = $2463.33

Total cost of loan = $25.97 × 104= $2700.88

Interest charged = total amount − loan
I = A − P
= 2700.88 − 2463.33
= 237.55

(0.75)31-0.75+0.75+(0.75)2+1=(0.75)3+(1-0.75)(1)2+(0.75)2+1×0.751-0.75 

= (0.75)3+(1)3-(0.75)31-0.75 =10.25=4=2

M = p(1+i)^n

Assume that the number is taken as XYZ.
Condition 1 => Z = sq.root(x) => Possible digits of X is 1,4,9
Condition 2 => Y = X + Z
X Y Z
1 2 1
4 6 2
9 12 3 => (wrong because it is 4 digit.)

and 121 is not divisible by 2

The answer is 462.

$$\begin{gathered} Given 3.2% of 500 × 2. 4% of ? = 312 \\ Then, \\ 3.2 x 500100 x 2.4 x ?100 = 312 \\ 16 x 2.4x?100 = 312 \\ 9.6 x ?25 = 312 \\ 9.6 x ? = 7800 \\ ? = 78009.6 \\ ? = 812.5 \end{gathered}$$

Probability is Number of favourable outcomes by total outcomes

Total comes = 2 (Divisible or not)

Favourable = 1 (Divisible)

Hence, probability = 1/2.