Question

1. Find the value of each of the following.
(i) Increase 90 by 10%.
(ii) Decrease 640 by 25%.
(ii) Increase 125 by 50%.
(iv) Decrease 75 by 40%.​

Answer 1

HERE IS UR ANSWER :-

( i ) Increase 90 by 10% .

Increase the number by 10% of its value.

Percentage increase = 10% × 90

New value = 90 + Percentage increase

= 90 + (10% × 90) =90 + 10% × 90

= (1 + 10%) × 90 = (100% + 10%) × 90

= 110% × 90 = 110 ÷ 100 × 90

= 110 × 90 ÷ 100 = 9,900 ÷ 100 = 99 .

( ii ) Decrease 640 by 25% .

Decrease number by 25% of its value.

Percentage decrease = 25% × 640

New value = 640 - Percentage decrease

= 640 - (25% × 640) = 640 - 25% × 640

= (1 - 25%) × 640 = (100% - 25%) × 640

= 75% × 640 = 75 ÷ 100 × 640

= 75 × 640 ÷ 100 = 48,000 ÷ 100 = 480 .

( iii ) Increase 125 by 50% .

Increase the number by 50% of its value.

Percentage increase = 50% × 125

New value = 125 + Percentage increase

= 125 + (50% × 125) = 125 + 50% × 125

= (1 + 50%) × 125 = (100% + 50%) × 125

= 150% × 125 = 150 ÷ 100 × 125

= 150 × 125 ÷ 100 = 18,750 ÷ 100 = 187.5 .

( iv ) Decrease 75 by 40 % .

Decrease number by 40% of its value.

Percentage decrease = 40% × 75

New value = 75 - Percentage decrease

= 75 - (40% × 75) = 75 - 40% × 75

= (1 - 40%) × 75 = (100% - 40%) × 75

= 60% × 75 = 60 ÷ 100 × 75

= 60 × 75 ÷ 100 = 4,500 ÷ 100 = 45 .

I hope it will be a good answer for u ❣️

kindly follow me plz plz and plzzzzzzzz mark my answer brilliant plzzzzzzz ....