Answer: It will take 175 seconds
Step-by-step explanation:
Let us try to take out the important information in the question:-
*** The toaster takes 35 seconds to make 4 slices of toast.
*** It takes 70 seconds to make 8 slices of toast
*** It also takes 105 seconds to make 12 slices.
*** We are required to calculate how long it may probably take the toaster to make 20 slices.
Since it takes the toaster 35 seconds to make 4 slices of toast and 70 seconds to make 8 slices, we can compare and predict the amount of time a certain number of slices can possibly be made:-
4 slices were made in 35 seconds, 8 slices were made in 70 seconds and 12 slices were made in 105 seconds.
A critical examination reveals that an average of 4 slices was processed or made in about 35 seconds. For every 35 more seconds, the toaster was able to make 4 more slices. We'll then calculate the time it takes the toaster to make 1 slice:
4 slices ---------- 35 seconds
1 slice ----------- ? seconds
1/4 × 35
= 35/4 seconds
Now, if 1 slice will be made in 35/4 seconds,
20 slices will be made in:
1 slice --------- 35/4 seconds
20 slices ------ ? seconds
(20/1) × 35/4
= 175 seconds
It will take the toaster about 175 seconds to make 20 slices.
