Try this option:
1 meter=1000 mm; 1 hour=60 min. From another side: 1 mm=0.001 m. and 1 min=1/60 h.
Using this rule:
620 mm/h=0.06*620 m/h=37.2 meters per hour.
answer: 0.06
Answer:
Total amount Silas and Raja has at first = $252
Step-by-step explanation:
Let,
Amount Silas had = x
Amount Raja had = y
According to given statement;
x = 3y Eqn 1
x-84 = y+42 Eqn 2
Putting value of x from Eqn 1 in Eqn 2
3y - 84 = y+42
3y-y = 42+84
2y = 126
Dividing both sides by 2

Putting y = 63 in Eqn 1
x = 63(3)
x = 189
Total amount they had = 189 + 63 = $252
Hence,
Total amount Silas and Raja has at first = $252
I’m pretty sure it’s number two in my opinion