Explanation

tot = (last - first + 2) ÷ 2

tot = (80 - 2 + 2) ÷ 2

tot = 80 ÷ 2

tot = 40

Total even numbers from 1 to 81 = 40

Explanation

Step 1: Calculate the total marks needed for an average of 85 over 5 exams.

Total marks needed=Average×Number of exams

Total marks needed=85×5

Total marks needed=425

Step 2: Calculate the sum of the marks from the first four exams.

78+85+90+92=345

Step 3: Subtract the sum of the first four exam marks from the total marks needed.

Marks needed in the fifth exam=425−345

Marks needed in the fifth exam=80

Explanation

To find the mean, add all the numbers (4 + 10 + 5 + 9 + 12 = 40) and then divide by the number of values (5).

The mean is 40 ÷ 5 = 8.

Explanation

It is given that the six children were born at the interval of 2 years ,

Let consider their age as-

x years ( age of youngest child)

( x+2) years ( age of 2nd child)

(x+4) years ( age of 3rd child )

(x+6) years (age of 4 th child)

(x+8) years ( age of 5th child)

( x+10) years ( age of 6th child)

Given- the sum of ages of 6 children is 60

therefore according to the question :-

( x+x+2+x+4+x+6+x+8+x+10) = 60

6x + 30= 60

6x = 60-30=30

x = 30/ 6 = 5

∴ The age of youngest child is 5

Explanation

Number of pizzas = 4 pizzas

The number of slices in each pizza = 8 slices

Total number of slices =  slices

4 x 8 = 32 slices

Next, we need to divide the total number of slices by the number of people to find out how many slices each person will get:

Number of people = 6 persons

Number of slices per person = Total number of slices / Number of people

Number of slices per person = 32/6 = 5 slices

Explanation

Explanation

7 km/hr is the correct answer.

Time =80min+100min=3hr Distance=9km+12km=21km Distance/time=21km/3hr=7km/hr

Explanation

To find the normal weight of an adult who is 5'6" tall using the formula 

w=5.5(20+d),

we need to determine the value of d, which represents the number of inches one's height exceeds 5 feet.

Since 5'6" is 6 inches more than 5 feet, 

d=6.

Substitute 

d=6 into the formula:

w=5.5(20+6)

w=5.5(26)

w=143

Therefore, the normal weight of an adult who is 5'6" tall is 143 pounds.

Explanation

To find the average, first simplify the fractions:

1/2, 2/4 = 1/2, 3/6 = 1/2

All fractions are equal to 1/2.

Average = (1/2 + 1/2 + 1/2) / 3 = (3/2) / 3 = 1/2

Explanation

x,x+2,x+4,x+6,x+8

4,6,8,10,12

average=4+6+8+10+12÷5

average is 8

ND27-5-2023