The total number of parts of the work is 1+ 2+ 3 = 6
That is, the work is divided into 3 portions as \(\cfrac { 1 }{ 6 } ,\cfrac { 2 }{ 6 } \) and \(\cfrac { 3 }{ 6 } \) .
Thus, the percentage of \(\quad \cfrac { { 1 }^{ th } }{ 6 } \quad \cfrac { 1 }{ 6 } \times 100\%=\cfrac { 100 }{ 6 }\% =16\cfrac { 2 }{ 3 }\% \) 
Similarly, the percentage of \(\cfrac { { 2 }^{ th } }{ 6 } \) portion of work would be \(\cfrac { 2 }{ 6 } \times 100\%=\cfrac { 200 }{ 6 }\% =33\cfrac { 1 }{ 3 }\% \) 
Similarly, the percentage of \(\cfrac { { 3 }^{ th } }{ 6 } \) portion of work would be \(\quad \cfrac { 3 }{ 6 } \times 100\%=\cfrac { 300 }{ 6 } =50\%\)

Let the quantity of alloy required be Q g
Then 26 % of Q = 260 g
\(\cfrac { 26 }{ 100 } \times Q=260g\) 
\(Q=\cfrac { 260\times 100 }{ 26 } g\) 
Q = 1000 g
Therefore, the required quantity of alloy is 1000 g.

Number of students absent on a particular day = 14% of 50
= \(\cfrac { 14 }{ 100 } \times 50=7\) 
Therefore, the number of students present = 50 − 7 = 43 students.

\(125\%=\cfrac { 125 }{ 100 } =\cfrac { 5 }{ 4 } \)

We have \(\\ \cfrac { 7 }{ 4 } =\cfrac { 7 }{ 4 } \times \cfrac { 100 }{ 100 } =\cfrac { 7 }{ 4 } \times 100\%=\cfrac { 700 }{ 4 }\% =175\%\)