Question

pleaseeeee help it's really urgent
any 2pleassseee​

Answer 1

Step-by-step explanation:

1)let the original speed be x km/h

time=distance/speed,

as the question says, earlier time will be greater than the new time, hence

earlier time-newer time=30min(or 1/2hr)

(90/x)-(90/(x+15))=1/2

simplying gives x^2 +15x-2700=0

solving for x gives, x=45 km/h

2)

Let the capacity of father be F work per day and that of tinu be T work per day.

then, ratio of both capacity is T:F=10:1

work w=F×1=T×10...(i)

they both complete the same work in 6 days

hence, (T+F)×6=work

(T+10T)×6=work

11T×6=work

T×66=work

so, T takes 66 days to complete the work