Metamath Proof Explorer


Theorem numlt

Description: Comparing two decimal integers (equal higher places). (Contributed by Mario Carneiro, 18-Feb-2014)

Ref Expression
Hypotheses numlt.1
|- T e. NN
numlt.2
|- A e. NN0
numlt.3
|- B e. NN0
numlt.4
|- C e. NN
numlt.5
|- B < C
Assertion numlt
|- ( ( T x. A ) + B ) < ( ( T x. A ) + C )

Proof

Step Hyp Ref Expression
1 numlt.1
 |-  T e. NN
2 numlt.2
 |-  A e. NN0
3 numlt.3
 |-  B e. NN0
4 numlt.4
 |-  C e. NN
5 numlt.5
 |-  B < C
6 3 nn0rei
 |-  B e. RR
7 4 nnrei
 |-  C e. RR
8 1 nnnn0i
 |-  T e. NN0
9 8 2 nn0mulcli
 |-  ( T x. A ) e. NN0
10 9 nn0rei
 |-  ( T x. A ) e. RR
11 6 7 10 ltadd2i
 |-  ( B < C <-> ( ( T x. A ) + B ) < ( ( T x. A ) + C ) )
12 5 11 mpbi
 |-  ( ( T x. A ) + B ) < ( ( T x. A ) + C )