NCERT 2022 | मानव नेत्र तथा रंगबिरंगा संसार - L14 | CLASS 10 विज्ञान Ruchi Ma'am| 10 AM

Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, and pipe C alone can empty the full tank in x hours. All the pipes were opened together at 10.30 a.m., but C was closed at 2:30 p.m. If the tank was full at 8:30 p.m. on the same day, then what is the value of x ? पाइप A और B किसी टंकी को क्रमशः 16 और 24 घंटे में भर सकते हैं , तथा पाइप C अकेला भरी हुई टंकी को x घने में खाली कर सकता है | सभी पाइपों को सुबह 10 : 30 बजे एक साथ चालू किया गया, लेकिन 2 : 30 pm में C को बंद कर दिया गया | यदि टंकी उसी दिन 8 :30 pm में भर गई, तो x का मान ज्ञात करें |

Consider the marks, out of 100, obtained by 51 students of a class in a test, given in Table 14.9. M a r k s"N u m b e r o f S t u d e n t s"0-10 5 10-20 10 20-30 4 30-40 6 40-50 7 50-60 3 60-70 2 70-80 2 80-90 3 90-100 9Tot a l 51 Draw a freque

I started on my bicycle at 7 a.m. to reach a certain place . After going a certain distance, my bicycle went out of order. Consequently, I rested for 35 minutes and came back to my house walking all the way. I reached my home at 1 p.m. If my cycling speed is 10 kmph and my walking speed is 1 kmph then on my bicycle I covered a distance of 4(61)/(66)k m b. 13 4/9k m c. 14 3/8k m d. 1(10)/(21)k m

Factorise the expressions. (i) ax^2 + bx (ii) 7p^2 + 21q^2 (iii) 2x^3 + 2xy^2 + 2xz^2 (iv) am^2 + bm^2 + bn^2 + an^2 (v) (lm + l) + m +1 (vi) y(y+z) + 9(y+z) (vii) 5y^2 - 20y - 8z + 2yz (viii) 10ab + 4a + 5b +2 (ix) 6xy - 4y + 6 - 9x