MongoDB - Query calculation and group multiple items - mongodb

Question

Let's say I have this data:
{"Plane":"5546","Time":"55.0", City:"LA"}
{"Plane":"5548","Time":"25.0", City:"CA"}
{"Plane":"5546","Time":"6.0", City:"LA"}
{"Plane":"5548","Time":"5.0", City:"CA"}
{"Plane":"5555","Time":"15.0", City:"XA"}
{"Plane":"5555","Time":"8.0", City:"XA"}
and more but I just visualize the data
I want to calculate and group all the time and plane, this is expected output:
{"_id:":["5546","LA"],"Sum":2,"LateRate":1,"Prob"0.5}
The sum is sum all the time, Late is sum all the time with time > "15" and Prob is Late/Sum
The code I have tried but it still is missing something:
db.Collection.aggregate([
{
$project: {
Sum: 1,
Late: {
$cond: [{ $gt: ["$Time", 15.0] }, 1, 0]
},
prob:1
}
},
{
$group:{
_id:{Plane:"$Plane", City:"$City"},
Sum: {$sum:1},
Late: {$sum: "$Late"}
}
},
{
$addFields: {
prob: {
"$divide": [
"$Late",
"$Sum"
]
}
}
},
])

Answer 1

db.collection.aggregate([
{
$project: {
Time: 1,
Late: {
$cond: [
{
$gt: [
{
$toDouble: "$Time"
},
15.0
]
},
"$Time",
0
]
},
prob: 1,
Plane: 1,
City: 1
}
},
{
$group: {
_id: {
Plane: "$Plane",
City: "$City"
},
Sum: {
$sum: {
"$toDouble": "$Time"
}
},
Late: {
$sum: {
$toDouble: "$Late"
}
}
}
},
{
$addFields: {
prob: {
"$divide": [
"$Late",
"$Sum"
]
}
}
}
])
Project limits the fields passed to the next stage
On string, you cannot perform all relational/arithmetic operations
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