Explanation

120 × 0.3 = 36

Explanation

The set of integers, denoted by Z, forms an abelian group under the operation of addition (+). This means that the following properties hold: 

• Closure: For any integers a, b, their sum a + b is also an integer.
• Associativity: (a + b) + c = a + (b + c) for any integers a, b, c.
• Commutativity: a + b = b + a for any integers a, b.
• Identity: There exists an identity element, which is 0, such that a + 0 = a for any integer a.
• Inverse: For each integer a, there exists an inverse element, which is -a, such that a + (-a) = 0.

The set of integers does not form a group under multiplication, because the inverse property does not hold (except for 1 and -1). Division is not even a binary operation on the set of integers, because it is not defined for all pairs of integers (e.g., 1/2 is not an integer).

Therefore, the correct answer is Addition.

Explanation

16(93)15=93

solution

16+15=31×3=93

*

14(78)12=78

solution

14+12=26×3=78

Explanation

 100 million ,= 100, 000 000

It contains 8 zeros.

Explanation

A tree is mentioned as 5th from both ends

Number of trees to the left of the given tree = 4

Number of trees to the right of the given tree = 4

Thus, total number of trees = 4 + 1 + 4 = 9

answer is 9

Explanation

To subtract fractions with the same denominator:

9/10 - 4/10 = (9 - 4)/10

= 5/10

= 1/2

Explanation

let   2nd rational number is =x

first rational number is = 4/5

According to given condition

x*4/5=-28/15

 5*4x/5=-28/15*5

1/4*4x=-28/3*1/4

x=-7/3

Explanation

We will use the man-hour concept here to solve this problem Formula: (M1 × d1 × h1)/ W1 = (M2 × d2 × h2)/ W2 Where M, d,h, W are numbers of men, number of days, number of hours and work done respectively. Calculation: (M1 × d1 × h1)/ W1 = (M2 × d2 × h2)/ W2 ⇒ (5 × 6 × 6)/10 = (12 × d2 × 8)/16 ⇒ 18 = 6 × d2 ⇒ d2 = 3 ⇒ Number of days to make 16 toys = 3 days

Explanation

Basic rate per hour = Re. (20/40) = Re. 1/2.

Overtime per hour = 125 % of Re. 1/2 = Re.5/8.

He worked x hours overtime.

Then 20 + 5/8 x = 25 (or) = 5/8 x = 5

X = 40/5 = 8 hours

=> he worked in all for (40 + 8) = 48 hours.

 

Explanation

Simplifying 9.5 * 4 = 0

Multiply 9.5 * 4 = 38 = 0

Solving 38 = 0