# Mental Ability-Basic Arithmetic (NCO- Cyber Olympiad Class 9): Questions 32 - 37 of 49

Get 1 year subscription: Access detailed explanations (illustrated with images and videos) to 410 questions. Access all new questions we will add tracking exam-pattern and syllabus changes. View Sample Explanation or View Features.

Rs. 300.00 or

## Question number: 32

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

The sum of two angles of a triangles is 80° and their difference is 10°, find all the angles of the triangle.

### Choices

Choice (4) Response

a.

25°, 35°, 110°

b.

60°, 58°, 70°

c.

45°, 45°, 90°

d.

45°, 35°, 100°

## Question number: 33

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

How much pure alcohol should be added to 400ml of a 15 % solution to make its strength 32%?

### Choices

Choice (4) Response

a.

100 ml

b.

95 ml

c.

90 ml

d.

80 ml

## Question number: 34

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

Given, , and find the value of the following expression correct up to three places of decimal: .

### Choices

Choice (4) Response

a.

3.78

b.

3.88

c.

-2.88

d.

-2.67

## Question number: 35

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

The bacteria in a culture grows by 20 % in the first hour, decreases by 10 % in the second hour and again increases by 20 % in the third hour. If at the end of the third hour the count of bacteria is 100000. The original count of bacteria in the sample is________

### Choices

Choice (4) Response

a.

129300

b.

129000

c.

129900

d.

129600

## Question number: 36

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

Sterling gold is 92.5 % pure gold. How many grams of sterling gold must be mixed to a 90 % gold alloy to obtain a 500 gm of a 91 % gold alloy?

### Choices

Choice (4) Response

a.

100 gm

b.

50 gm

c.

150 gm

d.

200 gm

## Question number: 37

» Mental Ability » Basic Arithmetic

MCQ▾

### Question

Given, , and find the value of the following expression correct up to three places of decimal: .

### Choices

Choice (4) Response

a.

-17

b.

-12

c.

-10

d.

-30

f Page