import Foundation

var line = readLine()!.components(separatedBy: " ").map { Int($0)! }
let A = line[0]
let V = line[1]
line = readLine()!.components(separatedBy: " ").map { Int($0)! }
let B = line[0]
let W = line[1]
let T = readLine()!.components(separatedBy: " ").map { Int($0)! }.first!

if V <= W || B < A {
    print("NO")
} else if B + W * T <= A + V * T {
    print("YES")
} else {
    print("NO")
}
