Question

A set of kitchen containers can be stacked to save space. The height of the stack is given by the expression LaTeX: 1.5c+7.61.5 c + 7.6 where c is the number of containers. What is the height of a stack made of 8 containers?____ cm A tower made of all the containers is 40.6 cm tall. How many containers are in the set?______ containers Noah looks at the equation and says, "7.6 must be the height of a single container." Do you agree with Noah? Explain your reasoning.

Answer 1

Part A

The height of the stack made of 8 containers is 19.6 cm

Part B

When the tower is 40.6 cm tall, the number of containers in the set are 22 containers

Part C

(Disagree) The height of a single container is 9.1

Explanation:

The question relates to containers, stacked one inside the other such that the height increases by only the wider top edge of the containers

The given expression that gives the height of the stack is presented as follows;

1.5·c + 7.6

Where;

c = The number of containers in the stack

Part A

When there are 8 containers, we have;

h(8) = 1.5 × 8 + 7.6 = 19.6

The height of the stack made of 8 containers, h(8) = 19.6 cm

Part B

When the tower (height of the stack set) is 40.6 cm tall, we have;

h(c) = 1.5·c + 7.6 = 40.6

∴ The number of containers, c = (40.6 - 7.6)/1.5 = 22

When the tower is 40.6 cm tall, the number of containers in the set, c = 22 containers

Part C

Given that the height stack increases only by the thickness of the wider rim of each added container, we have;

The expression for the height of the stack , 1.5·c + 7.6, is the expression for a straight line equation, m·x + c

The thickness of each rim = The slope, of the line, m = The increase in height with number of containers = 1.5

The number of containers (The independent variable, x) = The number of stacked rims = c

The minimum height = The height of a single container = 1.5 × 1 + 7.6 = 9.1

Therefore, the height of a single container = 9.1 not 7.6