Question

If the thickness of a pile of 12 cardboard sheets is 45 mm then how many sheets of the same cardboard would be 90 cm thick?​

Answer 1

Explanation:

45 mm / 12 sheet = 3.75 mm sheet

90 cm = 900 mm

900 mm / 3.75 mm/sheet = 240 sheets

Answer 2

Hello!

Answer:

`\Large \boxed{ \sf240}`

Explanation:

→ We want to find how many sheets of the same cardboard would be 90cm thick.

→ We know that the thickness of a pile of 12 cardboard sheets is 45 mm.

→ So we know that 1 cardboard is equal to 45/12 = 3.75mm

→ We also know that 90cm = 900mm.

→ So we have this table:

`\begin{tabular}{ l c r } Number of cardboard & 1 & x \\ Thickness (mm)& 3.75 & 900 \\ \end{tabular}`

→ Let's find x to find the number of sheets that would be 90cm thick.

→ Let's use the method of the cross:

`\sf x = 1 * 900 / 3.75 =\boxed{ \sf240}`

Conclusion:

There are 240 cardboard in a 90cm thick stack.