For the past three months, grace used her cell phone for 43 minutes, 62 minutes, and 57 minutes. how many minutes would she have to use her cell phone thur month for the average usage over the four months to be 55 minutes

She have to use her cell phone for 58 minutes in the fourth month.

Step-by-step explanation:

Since we have given that

Number of minutes Grace used her cell phone are as follows :

43 minutes, 62 minutes, 57 minutes, x.

Average = 55 minutes

As we know the formula for "Average":

Hence, She have to use her cell phone for 58 minutes in the fourth month.

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation: