There are n students, 86.4 n+(76-67) = 86.58 n = 50. There are (50) students in this class.
3. Let the walking speed be A, the cycling speed be B, and the distance from home to the station be S.
S=50a= 10b (S-9b)/a=b/a= 5。 It will take another five minutes.
4.198 ÷198/199+1200 What is this?
5.2007×200620062006-2006×200720072007
=2007*2006* 10^8+2007*2006* 10^4+2007*2006
-2006*2007* 10^8+2006*2007* 10^4+2006*2007=0
6. 19.8×59+ 1.98×6 10-2000×0. 198= 19.8*59+ 19.8*6 1-20* 19.8= 19.8*(59+6 1-20)= 19.8* 100= 1980
7.2008×2007200720072007/2008200820082008
=2008*(2007* 10^ 12+2007* 10^8+2007* 10^4+2007)/(2008* 10^ 12+2008* 10^8+2008* 10^4+2008)=
(2007* 10^ 12+2007* 10^8+2007* 10^4+2007)/( 10^ 12+ 10^8+ 10^4+ 1)=2007
8. 1×3×6+2×6× 12+3×9× 18/ 1×2×4+2×6× 12+3×6× 12
= 1×3×6*( 1+2+3)/ 1×2×4( 1+2+3)= 1×3×6/ 1×2×4=9/4
10. let b/a = 2/3 (b-8)/(a+8) = 1/2a = 72, b = 48 48/72,1,
Not rare to report 12
4. 198 divided by 198 and 189/ 199 plus 1 divided by 200 is a decimal, * and what is the operation symbol? 198÷ 198 198/ 199+ 1÷200 = 198÷( 198* 199+ 198)/ 199+ 1÷200 = 1 98÷( 198*200)/ 199+ 1 ÷ 200 = ( 198 * 199)/( 198 * 200)+ 1 ÷ 200 = 199
1. Some people drive 40 kilometers to work and 30 kilometers to work. It takes him 1 hour to drive to and from work, so he drives () kilometers to and from work, and the average commuting speed is () kilometers per hour.
2. Grade 6 1 class average score is 86.4. After review, it was found that the 76 points of Dawn were wrongly calculated as 67 points. After recalculation, the average review score is 86.58. There are () students in this class.
3. It takes 50 minutes for someone to walk from home to the station and 10 minutes by bike. On his way from home to the station, he left home for 9 minutes. After he parked his car at his grandmother's house, how long will it take him at least to walk to the station?
4. 198÷ 198 198/ 199+ 1÷200
5.2007×200620062006-2006×200720072007
6. 19.8×59+ 1.98×6 10-2000×0. 198
7.2008×2007200720072007/2008200820082008
8. 1×3×6+2×6× 12+3×9× 18/ 1×2×4+2×6× 12+3×6× 12
10. The score is 2/3. If the numerator of this fraction subtracts 8 and the denominator adds 8, the new fraction is 1/2. Find this score.