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.