Number System-Test 1

Answer: Option D

Explanation

Let the first number be x and second number be y

Then, 2(x²)=6y

x²=3y

∴ we cannot determine the ration between these two numbers.

Hnece, Option D is correct.

Answer: Option D

Explanation

Let the number be 'x'

Then, (2×x)+(3×42)=238 

or 2x=238-126

⇒ 2x=112

⇒ x=56

Now, (3×56)+(2×42)

=168+84=252.

Hence, Option D is correct.

Answer: Option E

Explanation

let the two numbers be x and y

Then,  

$$\begin{gathered} \Rightarrow \frac{3}{4}\times x=\frac{5}{6}\times y \\ \Rightarrow \frac{x}{y}=\frac{5}{6}\times \frac{4}{3}=\frac{20}{18}=10:9 \end{gathered}$$

Hence, Option D is correct.

Answer: Option A

Explanation

Let the two numbers be x and y

and 2x+3y=100

Again, 3x+2y=120

2x+3y=100  ---×2 (multiply by '2')

3x+2y=120  ---×3 (multiply by '3')

we get

4x+6y=200 ---Eq(1)

9x+6y=360 ---Eq(2)

By subracting Eq(1) and Eq(2) we get  

⇒ -5x=-160

⇒ x=32, y=12

Hence, larger number is 32.

Answer: Option E

Explanation

Let the five numbers be a, b, c, d and e.

And a+b+c+d+e+=290

Again, a+b=2×48.5=97

and d+e=2×53.5=107

So, a+b+c+d+e= 97+107=204

∴Third number =290-204=86

Hence, option D is correct.