libz.so.1: cannot open shared object file

After checking to which package does the libz.so.1 belongs (http://packages.ubuntu.com/lucid/i386/zlib1g/filelist) you should try to install zlib1g:

sudo apt-get install zlib1g

As pointed by @E-rich, it may be required to add a :i386 suffix to the package name for the package manager correctly identify it:

sudo apt-get install zlib1g:i386

EDIT (for CentOS or other distro that makes use of yum):

If someone using CentOS (or any other distro that makes use of yum) that may end up reading this question, @syslogic proposed the following solution in the comments:

yum install zlib.i686

or, for 32-bit binaries:

yum install zlib.i386

This worked for me

sudo apt-get install libc6-i386 lib32stdc++6 lib32gcc1 lib32ncurses5

For Fedora (can be useful for someone)

sudo dnf install zlib-1.2.8-10.fc24.i686 libgcc-6.1.1-2.fc24.i686

Check below link: Specially "Install 32 bit libraries (if you're on 64 bit)"

 https://github.com/meteor/meteor/wiki/Mobile-Dev-Install:-Android-on-Linux

sudo apt-get install zlib1g:i386 fixed the Gradle issue on Android 2.1.1 on Xubuntu 16.04.