Given, 2 marks are given for every right answer and 1 mark is deducted for each wrong anwser.

Shreya got 30 marks giving 16 correct answers.

Let us suppose the number of incorrect answers is y. Then,

Marks obtained by Shreya= Marks awarded for right answer × number of right answers + marks deducted for wrong answer × number of wrong answer.

[tex]30 = 2 \times 16 + ( - 1) \times y[/tex]

[tex]30 = 32 - y[/tex]

[tex] - 2 = - y[/tex]

[tex]y = 2[/tex]

So number of wrong answers by Shreya is 2