Make 2 equations one for the price and one for quantity. so first set x = AA and y= AAA. for price 37= 1x+.75y. now for the quantity we have x+y=42. Now we can solve by subtracting the equation for price from the equation for quantity and we get .25y =5. solving this we get y= 20. Now we plug that value back in and solve for x. 22 double A's and 20 triple A's.

6 0

4 years ago

A teenager’s heart pumps an average of 7200 L of blood every 24 hours. What is the rate of change of volume of blood?

love history [14]

Answer:

300L per hour

Step-by-step explanation:

The rate of change of volume of blood pumped by the teenager's heart expresses the volume of blood pumped with respect to hour.

Rate of change of volume of blood = $\frac{volume of blood}{time}$

= $\frac{7200L}{24}$

= 300L/hour

The rate of change of volume of blood by the teenager's heart is 300 litres per hour. This implies that his/ her heart pumps 300 litres of blood every hour.

7 0

3 years ago

Solve the simultaneous equations: 5x + 3y = 9 7x - 2y = 25 x=__ y=__

kondor19780726 [428]

Answer:

x= 3, y= -2

Step-by-step explanation:

5x+3y= 9

x= 25÷7 + 2÷7 y

5(25÷7 +2÷7 y)

5( 25÷7 +2÷7 y ) + 3y= 9

y= -2

x= 25÷7 + 2÷7 x (-2)

x= 3

5 0

3 years ago