80 विद्यार्थियों का एक समूह पिकनिक पर गया। इस समूह में \( 20 \% \) विद्यार्थी लड़कियाँ हैं तथा शेष लड़के हैं। इसमें कितनी और लड़कियाँ सम्मिलित की जाएँ कि समूह में लड़के \( 70 \% \) हो जाएँ? \( \begin{array}{ll}\text { (A) } 16 & \text { (B) } 24 \\ \text { (C) } 12 & \text { (D) } 8\end{array} \)

Anine løper ei løype på \( 12,35 \mathrm{~km} \). Inge løper samme løype to ganger. Hvor langt løper de til sammen?

If you applied the divisibility test for 8 to determine whether or not the natural number 304331543091 is divisible by 8 , you would check to see if 8 divides what number?

Use prime-factorization to find the greatest common divisor (also called greatest common factor) and least common multiple of 336 and 252 . \( \operatorname{gcd}(336,252)=\square \) \( \operatorname{lcm}(336,252)=\square \)

Bisa and Ibrahim both did their laundry today. Bisa does laundry every 5 days and Ibrahim does laundry every 10 days. How many days will it be until Bisa and Ibrahim both do laundry on the same day again? days

b) \( (7,521)(4,8)= \)