Question

A boy gets 3 marks for each correct sum and
loses 2 marks for each incorrect sum. He does
24 sums and obtains 37 marks. The number
of correct sums were:
(a) 20
d) 17 (c) 31
(d) 19​

Answer 1

Answer:

d is the answer

Step-by-step explanation:

Answer 2

GivEn:

• Gain marks for correct sum = 3
• Loss marks for incorrect sum = 2
• Total number of sum solved by boy = 24
• Total Marks obtained by boy = 37

To find:

• Number of correct sum

Solution:

Let the total number of correct sum be x

Then, the total number of correct sum is 24 - x

Now, According to the Question:

3(x) - 2(24 - x) = 37

3x - 48 + 2x = 37

5x - 48 = 37

5x = 37 + 48

5x = 85

x = 85/5

x = 17

∴ Hence, The number of correct sums is 17.

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We can also find,

Number of incorrect sum,

→ (24 - x)

→ 24 - 17

→ 7