Categories
Algebra Smart Math

[Smart Math] Algebra Problem 9

Here’s and example of a SMART MATH problem for ALGEBRA.

Algebra

Problem

A temporary worker engaged on a contract basis is paid $10 every day he attends work and $5 is deducted from his salary as a fine every day he remains absent. If in a month of 30 working days, he earns $240, for how many days was he absent from work that month?

  1. 12 days
  2. 5 days
  3. 4 days
  4. 3 days
  5. 2 days

The Usual Method

[contentblock id=google-adsense-post]

Let the number of days he remained absent be ‘x’.

Hence, number of days he was present = (30 – x)

Hence, (30-x)\times 10-x\times 5=240

\therefore 300-10x-5x=240

\therefore 300-15x=240

\therefore 15x=60

\therefore x=4days

(Ans: 3)

Estimated Time to arrive at the answer = 45 seconds.

Using Technique

[contentblock id=google-adsense-post]

If the worker remained absent, he not only loses $5 but also loses the $10 daily wage. Thus the net loss for the worker is $15 (10 + 5).

Had the worker attended work on all 30 days, his earning would have been 30 x 10 = $300. But his actual earning = $240. Hence, the difference = 300 – 240 = $60 is attributable to the number of days he was absent. Since, loss per day of absence = $ 15, so for a loss of $60, the worker was absent for 4 days.

(Ans: 3)

Estimated Time to arrive at the answer = 15 seconds.
[starrater tpl=10]

[contentblock id=smartmath-blockquote]

Leave a Reply

Your email address will not be published. Required fields are marked *