Not The Mathematical Kind Of Logs

To cut a log into 4 pieces, you use 3 cuts. To cut a log into 3 pieces, you use 2 cuts. So it will take two-thirds the time so, $\frac{2}{3}\times4=\frac{8}{3}$

This question is really tricky. 4 pieces doesn't mean anything here. What is important is the cut. It takes 4 minute to do 3 cuts so that the log will be separated into 4 pieces. So 1 cut takes $4\div 3=\frac{4}{3}$ minutes. To cut the log into 3 pieces, then you have to do 2 cuts, which means $\frac { 4 }{ 3 } \times 2=\frac { 8 }{ 3 }$ minutes.

4 pieces means 3 cuts. 3 pieces means 2 cuts Thus the answer is 4/3x2. = 8 / 3

To obtain 4 pieces you have preform 3 cuts

Thus;

$\large{t_c=\frac {t_T}{n_c}}$

where:

$t_c\space$ :is the time of each cut

$t_T\space$ : the total time of the process

$n_c\space$ : number of cuts

$\large{t_c=\frac43}$

in case of 3 pieces

$\large{t_T=n_c\times t_c=2*\frac43=\boxed{\color{#D61F06}{\frac83}}}$

we want to cut 3 times to make 4 pieces,

time taken =4 min (to make 4 pieces)

therefore time taken for single cut = 4/3 min

for two cuts(that is to make 3 pieces) =4/3 x 2 = 8/3 min

With each cut 1.33 mins went by so with 2 cut i.e. three pieces we have 2.66 or 8/3

Regla de tres. 3 cortes 4 mins, 2 cortes X mins. (2x4/3)

For 4 pieces 3 cuts are made and it takes 4 mins, so time to make 1 cut=4/3 min ATQ, WE NEED TO MAKE 2 CUTS to produce 3 pieces. Hence time required= (4/3)*2 = 8/3.

Each one cut =4/3 of min & 2 cuts need 2*4/3 min to make 3 pieces =>8/3

3 cuts needed for making 4 pieces so each cut takes 1.33 mins. For 3 pcs, 2 cuts needed which takes 2.66 mins

It takes 4 minutes to cut 4 pieces means 3 cuts. To have 3 pieces it is required to cut 2 times. So the time takes for making 3 pieces is (4/3)*2 = (8/3)

4 mins for 3 cuts , 1 cut requires 4/3 mins and 2 cut needs 8/3 mins

Nice trick question for those sleepy heads ....

for those trying to find a way to get round it and prove your wrong answer right, give up, the parallel and sequential stuff that idea right up (you could argue wear and tear and state the first cut of a new saw cuts the first piece in 1m 40 and the last in 1m 20 and therefore 3 pieces would be done in 3m) but your pushing your luck LOL

In this problem,I have used unitary method of problem solving. To cut a log into 4 pieces we need 3 cuts and to perform 3 cuts we 4 minutes. Therefore: 3 cuts can be performed in 4 minutes. 1 cut can be performed in 4/3 minutes. so, 2 cuts can be performed in 4/3*2=8/3 minutes

I used a proportion to solve

4 pieces=3 cuts

3 pieces=2 cuts

$\frac {4 (minutes)} {3 (cuts)}$ × $\frac {x (minutes)}{2 (cuts)}$

Cross multiply to get

8 × 3x

Solve for x and you're done :)

To cut a log into 4 pieces it will require making 3 cuts. 3 cuts ~~ 4 minutes.
=> 1 cut ~~ 4/3 minutes. For making 3 pieces it will require making 2 cuts.... 2 cuts ~~ 2 * 4/3 = 8/3.