I have a double chainring on my road bike but one of my chainring bolts has broken so I'm left with only 4 out of the 5 I'm supposed to have. Is it safe to ride? (just until replacements arrive)
As long as you don't take your bike on a long strenuous ride or torque the snot out of it, you should be OK. Make sure the remaining 4 are properly tightened. Normal commuting should be fine.