Table:
0
A
B
C
D
E
1
Owner
Class
Number in class
Road numbers
Built
2
SCT Logistics
SCT class
15
SCT001-SCT015
2007-2008
3
Downer Rail
LDP class
9
LDP001-LDP009
2009
4
Pacific National
TT class
34
TT01-TT08, TT101-TT126
2009-2011
5
Whitehaven Coal
WH class
3
WH001-WH003
2011
6
Genesee & Wyoming Australia
GWA class
10
GWA001-GWA010
2011-2012

Questions and formulas:
Question: What is the total number in class for the Whitehaven Coal?
Formula: SUMIFS(C1,A1,"whitehaven coal")
Formula2: SUMIFS(C2:C6,A2:A6,"whitehaven coal")
Level: easy
Question: What was built in a class with less than 10, and the Downer Rail owner?
Formula: LET(query1,LET(query1,FILTER(A1:E1,A1="downer rail"),SUMMARIZE(CHOOSECOLS(query1,5),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)<10))
Formula2: LET(query1,LET(query1,FILTER(A2:E6,A2:A6="downer rail"),SUMMARIZE(CHOOSECOLS(query1,5),SUMX(CHOOSECOLS(query1,3)))),FILTER(query1,CHOOSECOLS(query1,2)<10))
Level: hard
Question: Which class has more than 15 people in the class?
Formula: LET(query1,SUMMARIZE(B1,SUMX(C1)),FILTER(query1,CHOOSECOLS(query1,2)>15))
Formula2: LET(query1,SUMMARIZE(B2:B6,SUMX(C2:C6)),FILTER(query1,CHOOSECOLS(query1,2)>15))
Level: hard
Question: Who is the owner that built in 2009-2011?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,E1="2009-2011"),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E6,E2:E6="2009-2011"),1))
Level: medium