Putting div's on the same row - html

Question

It's my understanding that to make div's line up on the save row you just need to make sure the col-sm-#'s add up to 12.
This isn't working for me, and wherever I place the isCoop section in my code, it ends up beneath the row I want. I just want the isCoop section to appear on the same line as the div's above it in this class.
I've changed the col-sm-#'s with no results
<div class="form-group">
<div class="col-sm-1 required campaign-drpdwn">
<select id="campaign" class="form-control font-weight-bold" ng-options="value.key as value.label for value in vm.campaignOptions" ng-model="vm.campaignOption" ng-change="vm.selectCampaignBy()"></select>
</div>
<div class="col-sm-1 no-padding required-div">*</div>
<!--<label class="col-sm-2 control-label">Total Campaign Budget</label>-->
<div class="col-sm-1 input-group" ng-show="!vm.selectCampaign">
<span class="input-group-addon">$</span>
<input type="text" ng-model="vm.Budget" class="form-control col-sm-2" name="budget" id="txtCampaignBudget" placeholder="enter budget" ng-required="!vm.selectCampaign == true" ng-keydown="vm.KeyPressEvent($event,vm.Budget)" ng-blur="vm.formatNumberWithoutDollar(vm.Budget)">
</div>
<span id="budget-lblerror" class="col-sm-offset-1 color-red" ng-show="campaignform.budget.$invalid && (campaignform.budget.$touched || vm.submitted)">Not valid input!</span>
<-- isCoop section -->
<div class="col-sm-3">
<label for="IsCoop" class="col-sm-2 control-label">Coop</label>
<label class="radio-inline">
<input type="radio" ng-model="vm.IsCoop" ng-value="1" name="IsCoop" />Yes
</label>
<label class="radio-inline">
<input type="radio" ng-model="vm.IsCoop" ng-value="0" name="IsNotCoop" />No
</label>
</div>
</div>