Solution:

i) Let us assume the larger number is x and smaller number is y. Then we have following equations, as per question:

x = y + 26 and x = 3y

Substituting the value of x from second equation in the first equation, we get;

x = y + 26

Or, 3y = y + 26

Or, 2y = 26

Or, y = 13

Substituting the value of y in second equation, we get;

x = 3y

Or, x = 13 x 3 = 39

Hence, x = 39 and y = 13

ii)  Let us assume the larger angle is x and smaller angle is y. Then we have following equations;

x = y + 18 and x + y = 180o

Substituting the value of x from first equation in second equation, we get;

x + y = 180o

Or, y + 18 + y = 180o

Or, 2y = 180o - 18o = 162o

Or, y = 81o

Substituting the value of y in first equation, we get;

x = y + 18

Or, x = 81o + 18o = 99o

Hence, x = 99o and y = 81o

iii)  Let cost of each bat  =  Rs x

Cost of each ball  = Rs y

Given that coach of a cricket team buys 7 bats and 6 balls for Rs 3800.

So that 7x + 6y = 3800

6y = 3800 – 7x

Divide by 6 we get

y = (3800 – 7x) /6         … (1)

Given that she buys 3 bats and 5 balls for Rs 1750.so that

3x + 5y = 1750

Plug the value of y

3x + 5 ((3800 – 7x) /6) = 1750

Multiply by 6 we get

18 x  + 19000 – 35 x = 10500

-17x =10500 - 19000

-17x = -8500

x = - 8500 / - 17

x =  500

Plug this value in equation first we get

y = ( 3800 – 7 * 500) / 6

y = 300/6

y = 50

Hence cost of each bat = Rs 500 and cost of each balls is Rs 50