jim@jim-desktop:~$ sudo find / -name "pkg-config"
/snap/core/6673/usr/share/bash-completion/completions/pkg-config
/snap/core/6818/usr/share/bash-completion/completions/pkg-config
/snap/core/6531/usr/share/bash-completion/completions/pkg-config
find: ‘/run/user/1000/gvfs’: Permission denied
/home/jim/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/share/doc/gcc-linaro-arm-linux-gnueabihf-raspbian/html/pkg-config
/home/jim/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/share/doc/gcc-linaro-arm-linux-gnueabihf-raspbian/html/pkg-config
/usr/share/bash-completion/completions/pkg-config
/usr/share/doc/pkg-config

jim@jim-desktop:~$ dpkg -l "pkg-config"
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                        Version            Architecture       Description
+++-======================================
pi  pkg-config                  0.29.1-0ubuntu1    amd64              manage compile and link flags for libraries

jim@jim-desktop:~$ sudo apt install pkg-config
Reading package lists... Done
Building dependency tree
Reading state information... Done
pkg-config is already the newest version (0.29.1-0ubuntu1).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
jim@jim-desktop:~$