9 consists of 6 matches. 7 and 8 are the same as above.
So 1978=2647
(hollow triangle) plus (solid triangle) is not equal to 1 124, that is to say, its result is actually the matching number that makes up the number.
So the meter equals 2254.
(Hollow triangle) plus (Solid triangle) =2254.
(Hollow triangle) minus (Solid triangle) =2.
Twice the hollow triangle is equal to 2254+2=2256.
The hollow triangle is equal to 1 128.
The solid triangle is equal to 1 126.