CAT 2025 Quant was dominated by Algebra followed by Arithmetic. In Arithmetic, the questions were dominated by topics like Speed-time-distance, Mixture and Alligations. This year, there was a surprise. The questions from Geometry were relatively on the lower side as compared to the previous years. There were 8 TITA Qs this year. Overall this section was at a medium level of difficulty.
Question 21 : Let p, q and r be three natural numbers such that their sum is 900, and r is a perfect square whose value lies between 150 and 500. If p is not less than 0.3q and not more than 0.7q, then the sum of the maximum and minimum possible values of p is
Given:
\[
p+q+r=900
\]
and \(r\) is a perfect square between 150 and 500.
Also:
\[
0.3q\leq p\leq0.7q
\]
Since:
\[
q=900-r-p
\]
To maximize \(p\), take the minimum possible \(r\).
The smallest perfect square greater than 150 is:
\[
r=169
\]
Using the upper bound \(p\leq0.7q\):
\[
p\leq0.7(900-169-p)
\]
\[
1.7p\leq511.7
\]
\[
p\leq301
\]
Taking \(p=301\):
\[
q=900-169-301=430
\]
and \(301=0.7(430)\), so it is valid.
To minimize \(p\), take the maximum possible \(r\).
The largest perfect square below 500 is:
\[
r=484
\]
Using the lower bound \(p\geq0.3q\):
\[
p\geq0.3(900-484-p)
\]
\[
1.3p\geq124.8
\]
\[
p\geq96
\]
Taking \(p=96\):
\[
q=900-484-96=320
\]
and \(96=0.3(320)\), so it is valid.
Sum of maximum and minimum possible values:
\[
301+96=397
\]
Copyrights © All Rights Reserved by 2IIM.com - A Fermat Education Initiative.
Privacy Policy | Terms & Conditions
CAT® (Common Admission Test) is a registered trademark of the Indian
Institutes of Management. This website is not endorsed or approved by IIMs.
2IIM Online CAT Coaching
A Fermat Education Initiative,
19/43, MG Chakrapani St,
Sathya Garden, Saligramam, Chennai 600 093
Mobile: (91) 99626 48484 / 94459
38484
WhatsApp: WhatsApp Now
Email: info@2iim.com