A softball coach has ordered softballs for two different leagues. The Junior League uses
an 11-inch softball priced at $2.50 each. The Senior League uses a 12-inch softball
priced at $3.50 each. The softball coach ordered a total of 120 softballs for $350.

The number of 11-inch softball is 70 and the number of 12-inch softball is 50.

Step-by-step explanation:

Given that,

Let us assume,

Forming the equation to solve x and y values :

x + y = 120  (1)

2.5x + 3.5y = 350   (2)

Multiply eq(1) by 2.5 and subtract eq(2) from eq(1),

 2.5x +2.5y = 300

-(2.5x +3.5y = 350)

         -1y     =  -50

Therefore the value of y = 50.

The number of 12-inch softball is 50.

Substitute y=50 in eq(1),

x+50 = 120

x = 120-50

x = 70

The number of 11-inch softball is 70.

24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for