Add 15 to a number, the multiply the result by 3. then answer is the same as subtracting 4 from the number and multiplying the result by 5. Find the number.

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

Which expression shows the sum of the polynomials with like terms grouped together

An office supply company conducted a survey before marketing a new paper shredder designed for home use. in the survey, 80 % of the people who tried the shredder were satisfied with it. because of this high satisfaction rate, the company decided to market the new shredder. assume that 80 % of all people are satisfied with this shredder. during a certain month, 100 customers bought this shredder. find the probability that of these 100 customers, the number who are satisfied is 69 or fewer.