Question

Find the number of pairs of coprime numbers between 11 and 19 (both inclusive).

Asked in RRB Technician Grade III · 2026
LCM and HCF · Quantitative Aptitude
Exam PYQ4 Options
Quantitative AptitudeNumber SystemLCM and HCFLCM and HCF BothRRB Technician Grade III2026
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Quick Revision

For two numbers, HCF × LCM = Product of the numbers.

Correct AnswerCorrect option for this question
Option D — 28

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Questions Asked from HCF & LCM Word Problems in Previous Exams

See how often HCF & LCM Word Problems has appeared in previous-year questions across major government exams.

High Exam Frequency
12UPSC Questions Asked in These Years:2010, 2011, 2013, 2014, 2016, 2017, 2020, 2021, 2022, 2023, 2024, 2026
9SSC Questions Asked in These Years:2016, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
8Railways Questions Asked in These Years:2016, 2018, 2020, 2021, 2022, 2024, 2025, 2026
11State PSC Questions Asked in These Years:2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025
HCF & LCM Word Problems has appeared in 40 previous-year exam questions, most frequently in UPSC, State PSC and SSC.
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