I'm not good at graphing, but desmos.com is an online graphing calculator that works really well.
Answer: d=20/3
Step By Step:
Step 1, Simplify:
12-3/4(d+16)=-5
(-3/4)d+(12-12)=-5
(-3/4)d=-5
Step 2, Multiply each side by 4/(-3)
(4/-3)*(-3/4)d=(4/-3)*-5
d=20/3
For 100 people, we will need 100/25=4 times the listed quantities.
Saussage rolls = 50*4 = 200 saussage rolls
Sandwiches = 75*4 = 300 sandwiches
Samosas = 25*4 = 100 samosas
