Eleanor practiced playing his violin for 12 minutes. he has practiced 40% of the amount of time he needs to practice today how many more minutes does eleanor need to practice today?

18 mins

Step-by-step explanation:

if 12mins is 40%

then add 12mins again

12+12=24

so 24 is 80%

then divide 12 by 2 and add it to 24

12/2=6

24+6=30

eleanor practiced 30 mins with his violin per day

he has practiced 12 mins out of 30mins

so he has 18 mins more to practice

The correct are is 5.5 cm².

Step-by-step explanation:

First of all, Carlos calciulated the are of the rectangle correctly, only the are unit is wrong, it should be 3 cm².

He made a mistake calculating the area of a the triangle: The area of a triangle can be calculated by multiplying the base by the height by .

(Comment if you want a deeper explanation on where this comes from)

He mistakenly takes 4 cm for the height, but if you look carefully the height of the triangle in this case is 4 cm - 1.5 cm = 2.5 cm.

That gives for the area of the triangle.

Adding those two together gets you a total area of 5.5 cm².