function sumAndMultiply(a, b, c) {
  let summation = sum(sum(a,b)[0],c)[0];
  let multiplication= multiply(multiply(a,b)[0],c)[0];
  return [summation,multiplication, `${a} and ${b} and ${c} sum to ${summation}.`, `The product of ${a} and ${b} and ${c} is ${multiplication}.`]
}
testSumAndMultiply(4,7,5);