Question

Solve the following
Soham received 40 messages on his birthday. Of these, 90% were birthday greetings. How many other messages did he get besides the greetings?

Answer 1

Total number of messages received by Soham on his birthday = 40
Percentage of birthday greeting messages = 90%
So, percentage of other messages besides the greetings = (100 − 90)% = 10%
Suppose the number of other messages besides the greetings be x. Let us write in two forms, the ratio of the number of other messages besides greetings to the total number of messages received on birthday, obtain an equation and solve it. Then, we have
$\frac{x}{40}=\frac{10}{100}$
⇒$\frac{x}{40}\times 40=\frac{10}{100}\times 40$
⇒x = 4
∴ Soham received 4 other messages besides the greetings on his birthday.