is it 20?

If Maxi leaves 30 minutes before Pippa Maxi has traveled 20km

130-20=110km

110/80=$1\frac{3}{8}$ 

$1\frac{3}{8}$*40=55

55+20=75km

40x + 40(x - 0.5) = 130

x = 1.875

40x = 75